[cros] user_manager component - move UserManagerBase and UserManager

* Move UserManager test helper classes in their own files * Move RemoveUserDelegate to user_manager component * Move UserManager ownership to BrowserProcessPlatformPart * UserManager::Get() still stays but instance is explicitly initialized/cleared with instance->Initialize()|Destroy() * ScopedUserManagerEnabler / ScopedTestUserManager classes still work * Introduce ChromeUserManager base class (impl: ChromeUserManagerImpl) * ChromeUserManager adds getters for MultiProfileUserController, UserImageManager, SupervisedUserManager. All clients that were using these methods now access ChromeUserManager instance through ChromeUserManager::Get(). * FakeUserManager/MockUserManager implement ChromeUserManager * Move *UserFlow() methods out of UserManager to ChromeUserManager BUG=387614 TBR=thestig,benwells Review URL: https://codereview.chromium.org/444903002 git-svn-id: svn://svn.chromium.org/chrome/trunk/src@289827 0039d316-1c4b-4281-b951-d872f2087c98
author: nkostylev@chromium.org <nkostylev@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> 2014-08-15 09:22:58 +0000
committer: nkostylev@chromium.org <nkostylev@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> 2014-08-15 09:22:58 +0000
commit: b96c9db0b4ac10bf24c220149c074b5f27fe4a4f (patch)
tree: 305014dd85fd28832ebc1b5acda4865747583241
parent: 861bdb5554f52e520b302280f5fa0db14e74d9f7 (diff)
download: chromium_src-b96c9db0b4ac10bf24c220149c074b5f27fe4a4f.zip
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291 files changed, 3092 insertions, 2602 deletions
diff --git a/apps/DEPS b/apps/DEPS
index cfc3724..97f9cb0 100644
--- a/apps/DEPS
+++ b/apps/DEPS
@@ -6,6 +6,7 @@ include_rules = [
   "+content/public/test",
   "+components/keyed_service",
   "+components/pref_registry/pref_registry_syncable.h",
+  "+components/user_manager",
   "+components/web_modal",
   "+extensions",
   "+net/base",
diff --git a/apps/launcher.cc b/apps/launcher.cc
index ca463de..aabbc64 100644
--- a/apps/launcher.cc
+++ b/apps/launcher.cc
@@ -4,8 +4,8 @@
 
 #include "apps/launcher.h"
 
-#include <utility>
 #include <set>
+#include <utility>
 
 #include "base/command_line.h"
 #include "base/file_util.h"
@@ -40,7 +40,7 @@
 #include "url/gurl.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 namespace app_runtime = extensions::core_api::app_runtime;
@@ -318,7 +318,7 @@ void LaunchPlatformAppWithCommandLine(Profile* profile,
   if (extensions::KioskModeInfo::IsKioskOnly(extension)) {
     bool in_kiosk_mode = false;
 #if defined(OS_CHROMEOS)
-    chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+    user_manager::UserManager* user_manager = user_manager::UserManager::Get();
     in_kiosk_mode = user_manager && user_manager->IsLoggedInAsKioskApp();
 #endif
     if (!in_kiosk_mode) {
diff --git a/chrome/browser/DEPS b/chrome/browser/DEPS
index 7bf9348..2142b00 100644
--- a/chrome/browser/DEPS
+++ b/chrome/browser/DEPS
@@ -66,6 +66,7 @@ include_rules = [
   "+components/translate/core/browser",
   "+components/translate/core/common",
   "+components/url_matcher",
+  "+components/user_manager",
   "+components/user_prefs",
   "+components/web_modal",
   "+components/webdata/common",
diff --git a/chrome/browser/apps/app_browsertest.cc b/chrome/browser/apps/app_browsertest.cc
index cc78c10..a3572de 100644
--- a/chrome/browser/apps/app_browsertest.cc
+++ b/chrome/browser/apps/app_browsertest.cc
@@ -50,7 +50,7 @@
 #if defined(OS_CHROMEOS)
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/fake_dbus_thread_manager.h"
 #include "chromeos/dbus/fake_power_manager_client.h"
diff --git a/chrome/browser/background/background_mode_manager_unittest.cc b/chrome/browser/background/background_mode_manager_unittest.cc
index ec0d276..e1327aa 100644
--- a/chrome/browser/background/background_mode_manager_unittest.cc
+++ b/chrome/browser/background/background_mode_manager_unittest.cc
@@ -27,7 +27,7 @@
 #include "ui/message_center/message_center.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/browser_process_platform_part_chromeos.cc b/chrome/browser/browser_process_platform_part_chromeos.cc
index c6ce937..da30ee0 100644
--- a/chrome/browser/browser_process_platform_part_chromeos.cc
+++ b/chrome/browser/browser_process_platform_part_chromeos.cc
@@ -10,6 +10,7 @@
 #include "base/time/tick_clock.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/login/session/chrome_session_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager_impl.h"
 #include "chrome/browser/chromeos/memory/oom_priority_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
@@ -35,6 +36,18 @@ void BrowserProcessPlatformPart::ShutdownAutomaticRebootManager() {
   automatic_reboot_manager_.reset();
 }
 
+void BrowserProcessPlatformPart::InitializeChromeUserManager() {
+  DCHECK(!chrome_user_manager_);
+  chrome_user_manager_ =
+      chromeos::ChromeUserManagerImpl::CreateChromeUserManager();
+  chrome_user_manager_->Initialize();
+}
+
+void BrowserProcessPlatformPart::DestroyChromeUserManager() {
+  chrome_user_manager_->Destroy();
+  chrome_user_manager_.reset();
+}
+
 void BrowserProcessPlatformPart::InitializeSessionManager(
     const base::CommandLine& parsed_command_line,
     Profile* profile,
diff --git a/chrome/browser/browser_process_platform_part_chromeos.h b/chrome/browser/browser_process_platform_part_chromeos.h
index 8fe87aa..06e8b64 100644
--- a/chrome/browser/browser_process_platform_part_chromeos.h
+++ b/chrome/browser/browser_process_platform_part_chromeos.h
@@ -15,6 +15,7 @@ class CommandLine;
 }
 
 namespace chromeos {
+class ChromeUserManager;
 class OomPriorityManager;
 class ProfileHelper;
 }
@@ -45,6 +46,9 @@ class BrowserProcessPlatformPart : public BrowserProcessPlatformPartBase,
   void InitializeAutomaticRebootManager();
   void ShutdownAutomaticRebootManager();
 
+  void InitializeChromeUserManager();
+  void DestroyChromeUserManager();
+
   void InitializeSessionManager(const base::CommandLine& parsed_command_line,
                                 Profile* profile,
                                 bool is_running_test);
@@ -69,6 +73,10 @@ class BrowserProcessPlatformPart : public BrowserProcessPlatformPartBase,
 
   policy::BrowserPolicyConnectorChromeOS* browser_policy_connector_chromeos();
 
+  chromeos::ChromeUserManager* user_manager() {
+    return chrome_user_manager_.get();
+  }
+
   // Overridden from BrowserProcessPlatformPartBase:
   virtual void StartTearDown() OVERRIDE;
 
@@ -88,6 +96,8 @@ class BrowserProcessPlatformPart : public BrowserProcessPlatformPartBase,
   scoped_ptr<chromeos::system::AutomaticRebootManager>
       automatic_reboot_manager_;
 
+  scoped_ptr<chromeos::ChromeUserManager> chrome_user_manager_;
+
   DISALLOW_COPY_AND_ASSIGN(BrowserProcessPlatformPart);
 };
 
diff --git a/chrome/browser/browsing_data/browsing_data_remover.cc b/chrome/browser/browsing_data/browsing_data_remover.cc
index 27bd3fa..86db7fb 100644
--- a/chrome/browser/browsing_data/browsing_data_remover.cc
+++ b/chrome/browser/browsing_data/browsing_data_remover.cc
@@ -75,7 +75,6 @@
 #include "webkit/common/quota/quota_types.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chromeos/attestation/attestation_constants.h"
 #include "chromeos/dbus/cryptohome_client.h"
diff --git a/chrome/browser/browsing_data/browsing_data_remover_unittest.cc b/chrome/browser/browsing_data/browsing_data_remover_unittest.cc
index 3b0c8d8..15c5b01 100644
--- a/chrome/browser/browsing_data/browsing_data_remover_unittest.cc
+++ b/chrome/browser/browsing_data/browsing_data_remover_unittest.cc
@@ -55,7 +55,7 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
diff --git a/chrome/browser/chrome_browser_field_trials_desktop.cc b/chrome/browser/chrome_browser_field_trials_desktop.cc
index ac1cfe2..ce62911 100644
--- a/chrome/browser/chrome_browser_field_trials_desktop.cc
+++ b/chrome/browser/chrome_browser_field_trials_desktop.cc
@@ -27,10 +27,6 @@
 #include "net/spdy/spdy_session.h"
 #include "ui/base/layout.h"
 
-#if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
-#endif
-
 namespace chrome {
 
 namespace {
diff --git a/chrome/browser/chrome_content_browser_client.cc b/chrome/browser/chrome_content_browser_client.cc
index f10e0ae..17b99db 100644
--- a/chrome/browser/chrome_content_browser_client.cc
+++ b/chrome/browser/chrome_content_browser_client.cc
@@ -154,9 +154,9 @@
 #include "chrome/browser/chromeos/fileapi/file_system_backend.h"
 #include "chrome/browser/chromeos/fileapi/mtp_file_system_backend_delegate.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/system/input_device_settings.h"
 #include "chromeos/chromeos_switches.h"
+#include "components/user_manager/user_manager.h"
 #elif defined(OS_LINUX)
 #include "chrome/browser/chrome_browser_main_linux.h"
 #elif defined(OS_ANDROID)
@@ -390,7 +390,7 @@ bool HandleWebUI(GURL* url, content::BrowserContext* browser_context) {
   // Special case : in ChromeOS in Guest mode bookmarks and history are
   // disabled for security reasons. New tab page explains the reasons, so
   // we redirect user to new tab page.
-  if (chromeos::UserManager::Get()->IsLoggedInAsGuest()) {
+  if (user_manager::UserManager::Get()->IsLoggedInAsGuest()) {
     if (url->SchemeIs(content::kChromeUIScheme) &&
         (url->DomainIs(chrome::kChromeUIBookmarksHost) ||
          url->DomainIs(chrome::kChromeUIHistoryHost))) {
diff --git a/chrome/browser/chromeos/accessibility/accessibility_manager.cc b/chrome/browser/chromeos/accessibility/accessibility_manager.cc
index bdfa489..3a6089f 100644
--- a/chrome/browser/chromeos/accessibility/accessibility_manager.cc
+++ b/chrome/browser/chromeos/accessibility/accessibility_manager.cc
@@ -32,7 +32,6 @@
 #include "chrome/browser/chromeos/login/ui/login_display_host.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_view.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/component_loader.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ -48,6 +47,7 @@
 #include "chromeos/audio/chromeos_sounds.h"
 #include "chromeos/ime/input_method_manager.h"
 #include "chromeos/login/login_state.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_accessibility_state.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_details.h"
@@ -469,9 +469,8 @@ void AccessibilityManager::UpdateLargeCursorFromPref() {
 }
 
 bool AccessibilityManager::IsIncognitoAllowed() {
-  UserManager* user_manager = UserManager::Get();
   // Supervised users can't create incognito-mode windows.
-  return !(user_manager->IsLoggedInAsSupervisedUser());
+  return !(user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser());
 }
 
 bool AccessibilityManager::IsLargeCursorEnabled() {
diff --git a/chrome/browser/chromeos/accessibility/accessibility_manager_browsertest.cc b/chrome/browser/chromeos/accessibility/accessibility_manager_browsertest.cc
index cb3f8ea..b81ecee 100644
--- a/chrome/browser/chromeos/accessibility/accessibility_manager_browsertest.cc
+++ b/chrome/browser/chromeos/accessibility/accessibility_manager_browsertest.cc
@@ -13,7 +13,6 @@
 #include "chrome/browser/chromeos/accessibility/magnification_manager.h"
 #include "chrome/browser/chromeos/login/helper.h"
 #include "chrome/browser/chromeos/login/login_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/preferences.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/api/braille_display_private/mock_braille_controller.h"
@@ -28,6 +27,7 @@
 #include "chromeos/ime/component_extension_ime_manager.h"
 #include "chromeos/ime/input_method_manager.h"
 #include "chromeos/login/user_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/test/test_utils.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -272,7 +272,8 @@ IN_PROC_BROWSER_TEST_F(AccessibilityManagerTest, Login) {
   EXPECT_EQ(default_autoclick_delay(), GetAutoclickDelay());
 
   // Logs in.
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
 
   // Confirms that the features still disabled just after login.
   EXPECT_FALSE(IsLargeCursorEnabled());
@@ -282,7 +283,7 @@ IN_PROC_BROWSER_TEST_F(AccessibilityManagerTest, Login) {
   EXPECT_FALSE(IsVirtualKeyboardEnabled());
   EXPECT_EQ(default_autoclick_delay(), GetAutoclickDelay());
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that the features are still disabled just after login.
   EXPECT_FALSE(IsLargeCursorEnabled());
@@ -333,8 +334,9 @@ IN_PROC_BROWSER_TEST_F(AccessibilityManagerTest, BrailleOnLoginScreen) {
 
 IN_PROC_BROWSER_TEST_F(AccessibilityManagerTest, TypePref) {
   // Logs in.
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that the features are disabled just after login.
   EXPECT_FALSE(IsLargeCursorEnabled());
@@ -392,7 +394,8 @@ IN_PROC_BROWSER_TEST_F(AccessibilityManagerTest, TypePref) {
 
 IN_PROC_BROWSER_TEST_F(AccessibilityManagerTest, ResumeSavedPref) {
   // Loads the profile of the user.
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
 
   // Sets the pref to enable large cursor before login.
   SetLargeCursorEnabledPref(true);
@@ -420,7 +423,7 @@ IN_PROC_BROWSER_TEST_F(AccessibilityManagerTest, ResumeSavedPref) {
   EXPECT_FALSE(IsVirtualKeyboardEnabled());
 
   // Logs in.
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that features are enabled by restoring from pref just after login.
   EXPECT_TRUE(IsLargeCursorEnabled());
@@ -436,8 +439,9 @@ IN_PROC_BROWSER_TEST_F(AccessibilityManagerTest,
   MockAccessibilityObserver observer;
 
   // Logs in.
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->SessionStarted();
 
   EXPECT_FALSE(observer.observed());
   observer.reset();
@@ -495,8 +499,9 @@ IN_PROC_BROWSER_TEST_F(AccessibilityManagerTest,
   MockAccessibilityObserver observer;
 
   // Logs in.
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->SessionStarted();
 
   EXPECT_FALSE(observer.observed());
   observer.reset();
@@ -588,7 +593,7 @@ IN_PROC_BROWSER_TEST_P(AccessibilityManagerUserTypeTest,
 
   // Logs in.
   const char* user_name = GetParam();
-  UserManager::Get()->UserLoggedIn(user_name, user_name, true);
+  user_manager::UserManager::Get()->UserLoggedIn(user_name, user_name, true);
 
   // Confirms that the features are still enabled just after login.
   EXPECT_TRUE(IsLargeCursorEnabled());
@@ -597,7 +602,7 @@ IN_PROC_BROWSER_TEST_P(AccessibilityManagerUserTypeTest,
   EXPECT_TRUE(IsAutoclickEnabled());
   EXPECT_EQ(kTestAutoclickDelayMs, GetAutoclickDelay());
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that the features keep enabled after session starts.
   EXPECT_TRUE(IsLargeCursorEnabled());
@@ -617,13 +622,14 @@ IN_PROC_BROWSER_TEST_P(AccessibilityManagerUserTypeTest,
 IN_PROC_BROWSER_TEST_P(AccessibilityManagerUserTypeTest, BrailleWhenLoggedIn) {
   // Logs in.
   const char* user_name = GetParam();
-  UserManager::Get()->UserLoggedIn(user_name, user_name, true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->UserLoggedIn(user_name, user_name, true);
+  user_manager::UserManager::Get()->SessionStarted();
   // This object watches for IME preference changes and reflects those in
   // the IME framework state.
   chromeos::Preferences prefs;
-  prefs.InitUserPrefsForTesting(PrefServiceSyncable::FromProfile(GetProfile()),
-                                UserManager::Get()->GetActiveUser());
+  prefs.InitUserPrefsForTesting(
+      PrefServiceSyncable::FromProfile(GetProfile()),
+      user_manager::UserManager::Get()->GetActiveUser());
 
   // Make sure we start in the expected state.
   EXPECT_FALSE(IsBrailleImeActive());
@@ -660,8 +666,9 @@ IN_PROC_BROWSER_TEST_P(AccessibilityManagerUserTypeTest, BrailleWhenLoggedIn) {
 
 IN_PROC_BROWSER_TEST_F(AccessibilityManagerTest, AcessibilityMenuVisibility) {
   // Log in.
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that the features are disabled.
   EXPECT_FALSE(IsLargeCursorEnabled());
diff --git a/chrome/browser/chromeos/accessibility/magnification_manager.cc b/chrome/browser/chromeos/accessibility/magnification_manager.cc
index 0584e27..8f47444 100644
--- a/chrome/browser/chromeos/accessibility/magnification_manager.cc
+++ b/chrome/browser/chromeos/accessibility/magnification_manager.cc
@@ -18,7 +18,6 @@
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/accessibility/accessibility_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
diff --git a/chrome/browser/chromeos/accessibility/magnification_manager_browsertest.cc b/chrome/browser/chromeos/accessibility/magnification_manager_browsertest.cc
index 99921d9..719a633 100644
--- a/chrome/browser/chromeos/accessibility/magnification_manager_browsertest.cc
+++ b/chrome/browser/chromeos/accessibility/magnification_manager_browsertest.cc
@@ -14,7 +14,6 @@
 #include "chrome/browser/chromeos/accessibility/magnification_manager.h"
 #include "chrome/browser/chromeos/login/helper.h"
 #include "chrome/browser/chromeos/login/login_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/chrome_switches.h"
@@ -22,6 +21,7 @@
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chrome/test/base/testing_profile.h"
 #include "chromeos/chromeos_switches.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_prefs/user_prefs.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_service.h"
@@ -96,7 +96,7 @@ bool GetScreenMagnifierEnabledFromPref() {
 // the profile is regarded as "non new" in the next login. This is used in
 // PRE_XXX cases so that in the main XXX case we can test non new profiles.
 void PrepareNonNewProfile(const std::string& name) {
-  UserManager::Get()->UserLoggedIn(name, name, true);
+  user_manager::UserManager::Get()->UserLoggedIn(name, name, true);
   // To prepare a non-new profile for tests, we must ensure the profile
   // directory and the preference files are created, because that's what
   // Profile::IsNewProfile() checks. UserLoggedIn(), however, does not yet
@@ -184,12 +184,13 @@ IN_PROC_BROWSER_TEST_F(MagnificationManagerTest, LoginOffToOff) {
   EXPECT_FALSE(IsMagnifierEnabled());
 
   // Logs in with existing profile.
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
 
   // Confirms that magnifier is still disabled just after login.
   EXPECT_FALSE(IsMagnifierEnabled());
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that magnifier is still disabled just after session starts.
   EXPECT_FALSE(IsMagnifierEnabled());
@@ -223,13 +224,14 @@ IN_PROC_BROWSER_TEST_F(MagnificationManagerTest, LoginFullToOff) {
   EXPECT_EQ(2.5, GetFullScreenMagnifierScale());
 
   // Logs in (but the session is not started yet).
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
 
   // Confirms that magnifier is keeping enabled.
   EXPECT_TRUE(IsMagnifierEnabled());
   EXPECT_EQ(ash::MAGNIFIER_FULL, GetMagnifierType());
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that magnifier is disabled just after session start.
   EXPECT_FALSE(IsMagnifierEnabled());
@@ -252,12 +254,13 @@ IN_PROC_BROWSER_TEST_F(MagnificationManagerTest, LoginOffToFull) {
   EXPECT_FALSE(IsMagnifierEnabled());
 
   // Logs in (but the session is not started yet).
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
 
   // Confirms that magnifier is keeping disabled.
   EXPECT_FALSE(IsMagnifierEnabled());
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that the magnifier is enabled and configured according to the
   // explicitly set prefs just after session start.
@@ -287,13 +290,14 @@ IN_PROC_BROWSER_TEST_F(MagnificationManagerTest, LoginFullToFull) {
   EXPECT_EQ(3.0, GetFullScreenMagnifierScale());
 
   // Logs in (but the session is not started yet).
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
 
   // Confirms that magnifier is keeping enabled.
   EXPECT_TRUE(IsMagnifierEnabled());
   EXPECT_EQ(ash::MAGNIFIER_FULL, GetMagnifierType());
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that the magnifier is enabled and configured according to the
   // explicitly set prefs just after session start.
@@ -316,13 +320,14 @@ IN_PROC_BROWSER_TEST_F(MagnificationManagerTest, LoginFullToUnset) {
   EXPECT_EQ(ash::MAGNIFIER_FULL, GetMagnifierType());
 
   // Logs in (but the session is not started yet).
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
 
   // Confirms that magnifier is keeping enabled.
   EXPECT_TRUE(IsMagnifierEnabled());
   EXPECT_EQ(ash::MAGNIFIER_FULL, GetMagnifierType());
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that magnifier is disabled.
   EXPECT_FALSE(IsMagnifierEnabled());
@@ -337,12 +342,13 @@ IN_PROC_BROWSER_TEST_F(MagnificationManagerTest, LoginAsNewUserOff) {
   SetMagnifierEnabled(false);
 
   // Logs in (but the session is not started yet).
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
 
   // Confirms that magnifier is keeping disabled.
   EXPECT_FALSE(IsMagnifierEnabled());
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that magnifier is keeping disabled.
   EXPECT_FALSE(IsMagnifierEnabled());
@@ -359,13 +365,14 @@ IN_PROC_BROWSER_TEST_F(MagnificationManagerTest, LoginAsNewUserFull) {
   EXPECT_EQ(2.5, GetFullScreenMagnifierScale());
 
   // Logs in (but the session is not started yet).
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
 
   // Confirms that magnifier is keeping enabled.
   EXPECT_TRUE(IsMagnifierEnabled());
   EXPECT_EQ(ash::MAGNIFIER_FULL, GetMagnifierType());
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that magnifier keeps enabled.
   EXPECT_TRUE(IsMagnifierEnabled());
@@ -379,12 +386,13 @@ IN_PROC_BROWSER_TEST_F(MagnificationManagerTest, LoginAsNewUserUnset) {
   EXPECT_FALSE(IsMagnifierEnabled());
 
   // Logs in (but the session is not started yet).
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
 
   // Confirms that magnifier is keeping disabled.
   EXPECT_FALSE(IsMagnifierEnabled());
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that magnifier is keeping disabled.
   EXPECT_FALSE(IsMagnifierEnabled());
@@ -450,8 +458,9 @@ IN_PROC_BROWSER_TEST_F(MagnificationManagerTest, ChangeMagnifierType) {
 
 IN_PROC_BROWSER_TEST_F(MagnificationManagerTest, TypePref) {
   // Logs in
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that magnifier is disabled just after login.
   EXPECT_FALSE(IsMagnifierEnabled());
diff --git a/chrome/browser/chromeos/app_mode/app_session_lifetime.cc b/chrome/browser/chromeos/app_mode/app_session_lifetime.cc
index 6fa8455..7095824 100644
--- a/chrome/browser/chromeos/app_mode/app_session_lifetime.cc
+++ b/chrome/browser/chromeos/app_mode/app_session_lifetime.cc
@@ -15,7 +15,6 @@
 #include "chrome/browser/chromeos/app_mode/kiosk_app_update_service.h"
 #include "chrome/browser/chromeos/app_mode/kiosk_mode_idle_app_name_notification.h"
 #include "chrome/browser/chromeos/login/demo_mode/demo_app_launcher.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/browser/profiles/profile.h"
@@ -27,6 +26,7 @@
 #include "chrome/common/pref_names.h"
 #include "chromeos/network/network_state.h"
 #include "chromeos/network/network_state_handler.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/web_contents.h"
 
 using apps::AppWindowRegistry;
@@ -54,7 +54,7 @@ class AppWindowHandler : public AppWindowRegistry::Observer {
   virtual void OnAppWindowRemoved(apps::AppWindow* app_window) OVERRIDE {
     if (window_registry_->app_windows().empty()) {
       if (DemoAppLauncher::IsDemoAppSession(
-          chromeos::UserManager::Get()->GetActiveUser()->email())) {
+              user_manager::UserManager::Get()->GetActiveUser()->email())) {
         // If we were in demo mode, we disabled all our network technologies,
         // re-enable them.
         NetworkStateHandler* handler =
@@ -129,7 +129,7 @@ void InitAppSession(Profile* profile, const std::string& app_id) {
   // For a demo app, we don't need to either setup the update service or
   // the idle app name notification.
   if (DemoAppLauncher::IsDemoAppSession(
-      chromeos::UserManager::Get()->GetActiveUser()->email()))
+          user_manager::UserManager::Get()->GetActiveUser()->email()))
     return;
 
   // Set the app_id for the current instance of KioskAppUpdateService.
diff --git a/chrome/browser/chromeos/app_mode/kiosk_app_manager.cc b/chrome/browser/chromeos/app_mode/kiosk_app_manager.cc
index d5acb4c..e4e7b0e5 100644
--- a/chrome/browser/chromeos/app_mode/kiosk_app_manager.cc
+++ b/chrome/browser/chromeos/app_mode/kiosk_app_manager.cc
@@ -20,7 +20,6 @@
 #include "chrome/browser/chromeos/app_mode/kiosk_app_data.h"
 #include "chrome/browser/chromeos/app_mode/kiosk_app_external_loader.h"
 #include "chrome/browser/chromeos/app_mode/kiosk_app_manager_observer.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_local_account.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
diff --git a/chrome/browser/chromeos/app_mode/kiosk_mode_idle_app_name_notification.cc b/chrome/browser/chromeos/app_mode/kiosk_mode_idle_app_name_notification.cc
index c0cee0b..52cba04 100644
--- a/chrome/browser/chromeos/app_mode/kiosk_mode_idle_app_name_notification.cc
+++ b/chrome/browser/chromeos/app_mode/kiosk_mode_idle_app_name_notification.cc
@@ -8,12 +8,12 @@
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/ui/idle_app_name_notification_view.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/chrome_switches.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "extensions/browser/extension_system.h"
 #include "ui/wm/core/user_activity_detector.h"
 
@@ -68,7 +68,7 @@ KioskModeIdleAppNameNotification::~KioskModeIdleAppNameNotification() {
 }
 
 void KioskModeIdleAppNameNotification::Setup() {
-  DCHECK(UserManager::Get()->IsUserLoggedIn());
+  DCHECK(user_manager::UserManager::Get()->IsUserLoggedIn());
   Start();
 }
 
diff --git a/chrome/browser/chromeos/app_mode/startup_app_launcher.cc b/chrome/browser/chromeos/app_mode/startup_app_launcher.cc
index fcb46a4..5e7d1bf 100644
--- a/chrome/browser/chromeos/app_mode/startup_app_launcher.cc
+++ b/chrome/browser/chromeos/app_mode/startup_app_launcher.cc
@@ -15,7 +15,6 @@
 #include "chrome/browser/chromeos/app_mode/kiosk_app_manager.h"
 #include "chrome/browser/chromeos/app_mode/kiosk_diagnosis_runner.h"
 #include "chrome/browser/chromeos/login/session/user_session_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/install_tracker.h"
 #include "chrome/browser/extensions/install_tracker_factory.h"
@@ -30,6 +29,7 @@
 #include "chrome/common/extensions/manifest_url_handler.h"
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
 #include "components/signin/core/browser/signin_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "extensions/browser/extension_system.h"
@@ -333,7 +333,7 @@ void StartupAppLauncher::LaunchApp() {
                                   NEW_WINDOW));
   InitAppSession(profile_, app_id_);
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_KIOSK_APP_LAUNCHED,
diff --git a/chrome/browser/chromeos/attestation/platform_verification_flow.h b/chrome/browser/chromeos/attestation/platform_verification_flow.h
index 8c50312..b6571a4 100644
--- a/chrome/browser/chromeos/attestation/platform_verification_flow.h
+++ b/chrome/browser/chromeos/attestation/platform_verification_flow.h
@@ -37,7 +37,6 @@ class PrefRegistrySyncable;
 namespace chromeos {
 
 class CryptohomeClient;
-class UserManager;
 
 namespace attestation {
 
diff --git a/chrome/browser/chromeos/background/ash_user_wallpaper_delegate.cc b/chrome/browser/chromeos/background/ash_user_wallpaper_delegate.cc
index 717e495..4dc4584 100644
--- a/chrome/browser/chromeos/background/ash_user_wallpaper_delegate.cc
+++ b/chrome/browser/chromeos/background/ash_user_wallpaper_delegate.cc
@@ -12,12 +12,12 @@
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/extensions/wallpaper_manager_util.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/login/login_state.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 
 namespace chromeos {
@@ -106,7 +106,7 @@ class UserWallpaperDelegate : public ash::UserWallpaperDelegate {
       return false;
     }
     const user_manager::User* user =
-        chromeos::UserManager::Get()->GetActiveUser();
+        user_manager::UserManager::Get()->GetActiveUser();
     if (!user)
       return false;
     if (chromeos::WallpaperManager::Get()->IsPolicyControlled(user->email()))
diff --git a/chrome/browser/chromeos/boot_times_loader.cc b/chrome/browser/chromeos/boot_times_loader.cc
index db542f0..eb4633e 100644
--- a/chrome/browser/chromeos/boot_times_loader.cc
+++ b/chrome/browser/chromeos/boot_times_loader.cc
@@ -27,12 +27,12 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/auth/authentication_notification_details.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_iterator.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/notification_service.h"
@@ -514,7 +514,7 @@ void BootTimesLoader::Observe(
       if (render_widget_hosts_loading_.find(rwh) !=
           render_widget_hosts_loading_.end()) {
         AddLoginTimeMarker("TabPaint: " + GetTabUrl(rwh), false);
-        LoginDone(UserManager::Get()->IsCurrentUserNew());
+        LoginDone(user_manager::UserManager::Get()->IsCurrentUserNew());
       }
       break;
     }
diff --git a/chrome/browser/chromeos/chrome_browser_main_chromeos.cc b/chrome/browser/chromeos/chrome_browser_main_chromeos.cc
index b48fe8e..70d37a83 100644
--- a/chrome/browser/chromeos/chrome_browser_main_chromeos.cc
+++ b/chrome/browser/chromeos/chrome_browser_main_chromeos.cc
@@ -49,7 +49,7 @@
 #include "chrome/browser/chromeos/login/login_wizard.h"
 #include "chrome/browser/chromeos/login/session/user_session_manager.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/memory/oom_priority_manager.h"
@@ -107,6 +107,7 @@
 #include "components/metrics/metrics_service.h"
 #include "components/session_manager/core/session_manager.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/power_save_blocker.h"
@@ -341,7 +342,7 @@ void ChromeBrowserMainPartsChromeos::PreProfileInit() {
   // -- This used to be in ChromeBrowserMainParts::PreMainMessageLoopRun()
   // -- just before CreateProfile().
 
-  UserManager::Initialize();
+  g_browser_process->platform_part()->InitializeChromeUserManager();
 
   // Initialize the screen locker now so that it can receive
   // LOGIN_USER_CHANGED notification from UserManager.
@@ -415,7 +416,7 @@ void ChromeBrowserMainPartsChromeos::PreProfileInit() {
   if (immediate_login) {
     const std::string user_id = login::CanonicalizeUserID(
         parsed_command_line().GetSwitchValueASCII(switches::kLoginUser));
-    UserManager* user_manager = UserManager::Get();
+    user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
     if (policy::IsDeviceLocalAccountUser(user_id, NULL) &&
         !user_manager->IsKnownUser(user_id)) {
@@ -530,7 +531,7 @@ void ChromeBrowserMainPartsChromeos::PostProfileInit() {
 
   // Guest user profile is never initialized with locale settings,
   // so we need special handling for Guest session.
-  if (UserManager::Get()->IsLoggedInAsGuest())
+  if (user_manager::UserManager::Get()->IsLoggedInAsGuest())
     SetGuestLocale(profile());
 
   // These observers must be initialized after the profile because
@@ -692,7 +693,7 @@ void ChromeBrowserMainPartsChromeos::PostMainMessageLoopRun() {
   // of the CrosSettings singleton before it is destroyed. This also ensures
   // that the UserManager has no URLRequest pending (see
   // http://crbug.com/276659).
-  UserManager::Get()->Shutdown();
+  g_browser_process->platform_part()->user_manager()->Shutdown();
   WallpaperManager::Get()->Shutdown();
 
   // Let the AutomaticRebootManager unregister itself as an observer of several
@@ -724,7 +725,7 @@ void ChromeBrowserMainPartsChromeos::PostMainMessageLoopRun() {
   // parts of WebUI depends on NetworkPortalDetector.
   NetworkPortalDetector::Shutdown();
 
-  UserManager::Destroy();
+  g_browser_process->platform_part()->DestroyChromeUserManager();
 
   g_browser_process->platform_part()->ShutdownSessionManager();
 }
diff --git a/chrome/browser/chromeos/display/display_preferences.cc b/chrome/browser/chromeos/display/display_preferences.cc
index a9f7927..9614c15 100644
--- a/chrome/browser/chromeos/display/display_preferences.cc
+++ b/chrome/browser/chromeos/display/display_preferences.cc
@@ -17,8 +17,8 @@
 #include "base/strings/string_util.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/common/pref_names.h"
+#include "components/user_manager/user_manager.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
 #include "ui/gfx/display.h"
 #include "ui/gfx/insets.h"
@@ -98,7 +98,7 @@ ash::DisplayManager* GetDisplayManager() {
 // Returns true id the current user can write display preferences to
 // Local State.
 bool UserCanSaveDisplayPreference() {
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   return user_manager->IsUserLoggedIn() &&
       (user_manager->IsLoggedInAsRegularUser() ||
        user_manager->IsLoggedInAsSupervisedUser() ||
diff --git a/chrome/browser/chromeos/display/display_preferences_unittest.cc b/chrome/browser/chromeos/display/display_preferences_unittest.cc
index 7a0f998..658ec54 100644
--- a/chrome/browser/chromeos/display/display_preferences_unittest.cc
+++ b/chrome/browser/chromeos/display/display_preferences_unittest.cc
@@ -22,7 +22,7 @@
 #include "base/values.h"
 #include "chrome/browser/chromeos/display/display_configuration_observer.h"
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_browser_process.h"
 #include "ui/display/chromeos/display_configurator.h"
diff --git a/chrome/browser/chromeos/drive/drive_notification_manager_factory_browsertest.cc b/chrome/browser/chromeos/drive/drive_notification_manager_factory_browsertest.cc
index 6773e65..3ce0b1b 100644
--- a/chrome/browser/chromeos/drive/drive_notification_manager_factory_browsertest.cc
+++ b/chrome/browser/chromeos/drive/drive_notification_manager_factory_browsertest.cc
@@ -6,13 +6,13 @@
 
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/login/user_names.h"
+#include "components/user_manager/user_manager.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace drive {
@@ -52,7 +52,7 @@ class DriveNotificationManagerFactoryGuestBrowserTest
 // profile or the guest profile while a guest session is in progress.
 IN_PROC_BROWSER_TEST_F(DriveNotificationManagerFactoryGuestBrowserTest,
                        NoDriveNotificationManager) {
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   EXPECT_TRUE(user_manager->IsLoggedInAsGuest());
   Profile* guest_profile =
       chromeos::ProfileHelper::Get()
diff --git a/chrome/browser/chromeos/drive/file_system_util.cc b/chrome/browser/chromeos/drive/file_system_util.cc
index f20dbf7..db8043c 100644
--- a/chrome/browser/chromeos/drive/file_system_util.cc
+++ b/chrome/browser/chromeos/drive/file_system_util.cc
@@ -36,6 +36,7 @@
 #include "chrome/common/pref_names.h"
 #include "chrome/common/url_constants.h"
 #include "chromeos/chromeos_constants.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "net/base/escape.h"
 #include "webkit/browser/fileapi/file_system_url.h"
@@ -121,7 +122,7 @@ base::FilePath GetDriveMountPointPath(Profile* profile) {
     // returns currently active users's hash in such a case.) I still try
     // ProfileHelper first because it works better in tests.
     user_manager::User* const user =
-        chromeos::UserManager::IsInitialized()
+        user_manager::UserManager::IsInitialized()
             ? chromeos::ProfileHelper::Get()->GetUserByProfile(
                   profile->GetOriginalProfile())
             : NULL;
diff --git a/chrome/browser/chromeos/events/event_rewriter.cc b/chrome/browser/chromeos/events/event_rewriter.cc
index 62cff07..314a3ec 100644
--- a/chrome/browser/chromeos/events/event_rewriter.cc
+++ b/chrome/browser/chromeos/events/event_rewriter.cc
@@ -16,12 +16,12 @@
 #include "base/strings/string_util.h"
 #include "base/sys_info.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/ime/ime_keyboard.h"
 #include "chromeos/ime/input_method_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "ui/events/event.h"
 #include "ui/events/event_utils.h"
 #include "ui/events/keycodes/keyboard_code_conversion.h"
@@ -510,7 +510,7 @@ void EventRewriter::RewriteModifierKeys(const ui::KeyEvent& key_event,
   // TODO(glotov): remove the following condition when we do not restart chrome
   // when user logs in as guest.
   // TODO(kpschoedel): check whether this is still necessary.
-  if (UserManager::Get()->IsLoggedInAsGuest() &&
+  if (user_manager::UserManager::Get()->IsLoggedInAsGuest() &&
       LoginDisplayHostImpl::default_host())
     return;
 
diff --git a/chrome/browser/chromeos/events/event_rewriter_unittest.cc b/chrome/browser/chromeos/events/event_rewriter_unittest.cc
index f3e2b43..db71419 100644
--- a/chrome/browser/chromeos/events/event_rewriter_unittest.cc
+++ b/chrome/browser/chromeos/events/event_rewriter_unittest.cc
@@ -18,7 +18,7 @@
 #include "chrome/browser/chromeos/input_method/input_method_configuration.h"
 #include "chrome/browser/chromeos/input_method/mock_input_method_manager.h"
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/preferences.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_pref_service_syncable.h"
diff --git a/chrome/browser/chromeos/events/keyboard_driven_event_rewriter.cc b/chrome/browser/chromeos/events/keyboard_driven_event_rewriter.cc
index 14e3927..1b33924 100644
--- a/chrome/browser/chromeos/events/keyboard_driven_event_rewriter.cc
+++ b/chrome/browser/chromeos/events/keyboard_driven_event_rewriter.cc
@@ -5,8 +5,8 @@
 #include "chrome/browser/chromeos/events/keyboard_driven_event_rewriter.h"
 
 #include "chrome/browser/chromeos/events/event_rewriter.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/system/input_device_settings.h"
+#include "components/user_manager/user_manager.h"
 #include "ui/events/event.h"
 #include "ui/events/event_utils.h"
 
@@ -19,8 +19,8 @@ const int kModifierMask = ui::EF_SHIFT_DOWN;
 // Returns true if and only if it is on login screen (i.e. user is not logged
 // in) and the keyboard driven flag in the OEM manifest is on.
 bool ShouldStripModifiersForArrowKeysAndEnter() {
-  if (UserManager::IsInitialized() &&
-      !UserManager::Get()->IsSessionStarted()) {
+  if (user_manager::UserManager::IsInitialized() &&
+      !user_manager::UserManager::Get()->IsSessionStarted()) {
     return system::InputDeviceSettings::Get()
         ->ForceKeyboardDrivenUINavigation();
   }
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_misc.cc b/chrome/browser/chromeos/extensions/file_manager/private_api_misc.cc
index 14567a4..094e5ff 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_misc.cc
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_misc.cc
@@ -18,7 +18,6 @@
 #include "chrome/browser/chromeos/extensions/file_manager/private_api_util.h"
 #include "chrome/browser/chromeos/file_manager/app_installer.h"
 #include "chrome/browser/chromeos/file_manager/zip_file_creator.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/devtools/devtools_window.h"
@@ -36,6 +35,7 @@
 #include "chrome/common/pref_names.h"
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
 #include "components/signin/core/browser/signin_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/page_zoom.h"
@@ -63,7 +63,7 @@ apps::AppWindow* GetCurrentAppWindow(ChromeSyncExtensionFunction* function) {
 
 std::vector<linked_ptr<api::file_browser_private::ProfileInfo> >
 GetLoggedInProfileInfoList(content::WebContents* contents) {
-  DCHECK(chromeos::UserManager::IsInitialized());
+  DCHECK(user_manager::UserManager::IsInitialized());
   const std::vector<Profile*>& profiles =
       g_browser_process->profile_manager()->GetLoadedProfiles();
   std::set<Profile*> original_profiles;
@@ -112,7 +112,7 @@ bool FileBrowserPrivateLogoutUserForReauthenticationFunction::RunSync() {
   user_manager::User* user =
       chromeos::ProfileHelper::Get()->GetUserByProfile(GetProfile());
   if (user) {
-    chromeos::UserManager::Get()->SaveUserOAuthStatus(
+    user_manager::UserManager::Get()->SaveUserOAuthStatus(
         user->email(), user_manager::User::OAUTH2_TOKEN_STATUS_INVALID);
   }
 
diff --git a/chrome/browser/chromeos/extensions/info_private_api.cc b/chrome/browser/chromeos/extensions/info_private_api.cc
index c62e648..dbe59d1 100644
--- a/chrome/browser/chromeos/extensions/info_private_api.cc
+++ b/chrome/browser/chromeos/extensions/info_private_api.cc
@@ -11,7 +11,6 @@
 #include "chrome/browser/app_mode/app_mode_utils.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/system/timezone_util.h"
@@ -23,6 +22,7 @@
 #include "chromeos/settings/cros_settings_names.h"
 #include "chromeos/system/statistics_provider.h"
 #include "components/metrics/metrics_service.h"
+#include "components/user_manager/user_manager.h"
 #include "extensions/common/error_utils.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
 
@@ -182,7 +182,7 @@ base::Value* ChromeosInfoPrivateGetFunction::GetValue(
     return new base::StringValue(base::SysInfo::GetLsbReleaseBoard());
   } else if (property_name == kPropertyOwner) {
     return new base::FundamentalValue(
-        chromeos::UserManager::Get()->IsCurrentUserOwner());
+        user_manager::UserManager::Get()->IsCurrentUserOwner());
   } else if (property_name == kPropertyClientId) {
     return new base::StringValue(GetClientId());
   } else if (property_name == kPropertyTimezone) {
diff --git a/chrome/browser/chromeos/extensions/wallpaper_api.cc b/chrome/browser/chromeos/extensions/wallpaper_api.cc
index 1b1ae37..e994f2d 100644
--- a/chrome/browser/chromeos/extensions/wallpaper_api.cc
+++ b/chrome/browser/chromeos/extensions/wallpaper_api.cc
@@ -12,13 +12,13 @@
 #include "base/strings/stringprintf.h"
 #include "base/threading/worker_pool.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/pref_names.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "net/base/load_flags.h"
 #include "net/http/http_status_code.h"
 #include "net/url_request/url_fetcher.h"
@@ -100,9 +100,9 @@ bool WallpaperSetWallpaperFunction::RunAsync() {
   EXTENSION_FUNCTION_VALIDATE(params_);
 
   // Gets email address and username hash while at UI thread.
-  user_id_ = chromeos::UserManager::Get()->GetLoggedInUser()->email();
+  user_id_ = user_manager::UserManager::Get()->GetLoggedInUser()->email();
   user_id_hash_ =
-      chromeos::UserManager::Get()->GetLoggedInUser()->username_hash();
+      user_manager::UserManager::Get()->GetLoggedInUser()->username_hash();
 
   if (params_->details.wallpaper_data) {
     StartDecode(*params_->details.wallpaper_data);
@@ -138,7 +138,7 @@ void WallpaperSetWallpaperFunction::OnWallpaperDecoded(
   ash::WallpaperLayout layout = wallpaper_api_util::GetLayoutEnum(
       set_wallpaper::Params::Details::ToString(params_->details.layout));
   bool update_wallpaper =
-      user_id_ == chromeos::UserManager::Get()->GetActiveUser()->email();
+      user_id_ == user_manager::UserManager::Get()->GetActiveUser()->email();
   wallpaper_manager->SetCustomWallpaper(user_id_,
                                         user_id_hash_,
                                         params_->details.name,
diff --git a/chrome/browser/chromeos/extensions/wallpaper_private_api.cc b/chrome/browser/chromeos/extensions/wallpaper_private_api.cc
index a9b181a..045fa11 100644
--- a/chrome/browser/chromeos/extensions/wallpaper_private_api.cc
+++ b/chrome/browser/chromeos/extensions/wallpaper_private_api.cc
@@ -22,7 +22,6 @@
 #include "base/strings/stringprintf.h"
 #include "base/threading/worker_pool.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/chrome_paths.h"
@@ -30,6 +29,7 @@
 #include "chrome/grit/generated_resources.h"
 #include "chrome/grit/platform_locale_settings.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "extensions/browser/event_router.h"
 #include "ui/base/l10n/l10n_util.h"
@@ -301,7 +301,7 @@ bool WallpaperPrivateSetWallpaperIfExistsFunction::RunAsync() {
   params = set_wallpaper_if_exists::Params::Create(*args_);
   EXTENSION_FUNCTION_VALIDATE(params);
 
-  user_id_ = chromeos::UserManager::Get()->GetActiveUser()->email();
+  user_id_ = user_manager::UserManager::Get()->GetActiveUser()->email();
 
   base::FilePath wallpaper_path;
   base::FilePath fallback_path;
@@ -372,11 +372,11 @@ void WallpaperPrivateSetWallpaperIfExistsFunction::OnWallpaperDecoded(
       wallpaper_private::ToString(params->layout));
 
   bool update_wallpaper =
-      user_id_ == chromeos::UserManager::Get()->GetActiveUser()->email();
+      user_id_ == user_manager::UserManager::Get()->GetActiveUser()->email();
   wallpaper_manager->SetWallpaperFromImageSkia(
       user_id_, image, layout, update_wallpaper);
-  bool is_persistent =
-      !chromeos::UserManager::Get()->IsCurrentUserNonCryptohomeDataEphemeral();
+  bool is_persistent = !user_manager::UserManager::Get()
+                            ->IsCurrentUserNonCryptohomeDataEphemeral();
   chromeos::WallpaperInfo info = {params->url, layout,
                                   user_manager::User::ONLINE,
                                   base::Time::Now().LocalMidnight()};
@@ -408,7 +408,7 @@ bool WallpaperPrivateSetWallpaperFunction::RunAsync() {
   EXTENSION_FUNCTION_VALIDATE(params);
 
   // Gets email address while at UI thread.
-  user_id_ = chromeos::UserManager::Get()->GetActiveUser()->email();
+  user_id_ = user_manager::UserManager::Get()->GetActiveUser()->email();
 
   StartDecode(params->wallpaper);
 
@@ -482,12 +482,12 @@ void WallpaperPrivateSetWallpaperFunction::SetDecodedWallpaper(
       wallpaper_private::ToString(params->layout));
 
   bool update_wallpaper =
-      user_id_ == chromeos::UserManager::Get()->GetActiveUser()->email();
+      user_id_ == user_manager::UserManager::Get()->GetActiveUser()->email();
   wallpaper_manager->SetWallpaperFromImageSkia(
       user_id_, *image.get(), layout, update_wallpaper);
 
-  bool is_persistent =
-      !chromeos::UserManager::Get()->IsCurrentUserNonCryptohomeDataEphemeral();
+  bool is_persistent = !user_manager::UserManager::Get()
+                            ->IsCurrentUserNonCryptohomeDataEphemeral();
   chromeos::WallpaperInfo info = {params->url, layout,
                                   user_manager::User::ONLINE,
                                   base::Time::Now().LocalMidnight()};
@@ -510,7 +510,7 @@ WallpaperPrivateResetWallpaperFunction::
 bool WallpaperPrivateResetWallpaperFunction::RunAsync() {
   chromeos::WallpaperManager* wallpaper_manager =
       chromeos::WallpaperManager::Get();
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
   std::string user_id = user_manager->GetActiveUser()->email();
   wallpaper_manager->RemoveUserWallpaperInfo(user_id);
@@ -544,9 +544,9 @@ bool WallpaperPrivateSetCustomWallpaperFunction::RunAsync() {
   EXTENSION_FUNCTION_VALIDATE(params);
 
   // Gets email address and username hash while at UI thread.
-  user_id_ = chromeos::UserManager::Get()->GetActiveUser()->email();
+  user_id_ = user_manager::UserManager::Get()->GetActiveUser()->email();
   user_id_hash_ =
-      chromeos::UserManager::Get()->GetActiveUser()->username_hash();
+      user_manager::UserManager::Get()->GetActiveUser()->username_hash();
 
   StartDecode(params->wallpaper);
 
@@ -571,7 +571,7 @@ void WallpaperPrivateSetCustomWallpaperFunction::OnWallpaperDecoded(
       wallpaper_private::ToString(params->layout));
 
   bool update_wallpaper =
-      user_id_ == chromeos::UserManager::Get()->GetActiveUser()->email();
+      user_id_ == user_manager::UserManager::Get()->GetActiveUser()->email();
   wallpaper_manager->SetCustomWallpaper(user_id_,
                                         user_id_hash_,
                                         params->file_name,
@@ -655,9 +655,10 @@ bool WallpaperPrivateSetCustomWallpaperLayoutFunction::RunAsync() {
   info.layout = wallpaper_api_util::GetLayoutEnum(
       wallpaper_private::ToString(params->layout));
 
-  std::string email = chromeos::UserManager::Get()->GetActiveUser()->email();
-  bool is_persistent =
-      !chromeos::UserManager::Get()->IsCurrentUserNonCryptohomeDataEphemeral();
+  std::string email =
+      user_manager::UserManager::Get()->GetActiveUser()->email();
+  bool is_persistent = !user_manager::UserManager::Get()
+                            ->IsCurrentUserNonCryptohomeDataEphemeral();
   wallpaper_manager->SetUserWallpaperInfo(email, info, is_persistent);
   wallpaper_manager->UpdateWallpaper(false /* clear_cache */);
   SendResponse(true);
@@ -676,7 +677,7 @@ WallpaperPrivateMinimizeInactiveWindowsFunction::
 
 bool WallpaperPrivateMinimizeInactiveWindowsFunction::RunAsync() {
   WindowStateManager::MinimizeInactiveWindows(
-      chromeos::UserManager::Get()->GetActiveUser()->username_hash());
+      user_manager::UserManager::Get()->GetActiveUser()->username_hash());
   return true;
 }
 
@@ -690,7 +691,7 @@ WallpaperPrivateRestoreMinimizedWindowsFunction::
 
 bool WallpaperPrivateRestoreMinimizedWindowsFunction::RunAsync() {
   WindowStateManager::RestoreWindows(
-      chromeos::UserManager::Get()->GetActiveUser()->username_hash());
+      user_manager::UserManager::Get()->GetActiveUser()->username_hash());
   return true;
 }
 
@@ -706,7 +707,8 @@ bool WallpaperPrivateGetThumbnailFunction::RunAsync() {
   EXTENSION_FUNCTION_VALIDATE(params);
 
   base::FilePath thumbnail_path;
-  std::string email = chromeos::UserManager::Get()->GetActiveUser()->email();
+  std::string email =
+      user_manager::UserManager::Get()->GetActiveUser()->email();
   if (params->source == get_thumbnail::Params::SOURCE_ONLINE) {
     std::string file_name = GURL(params->url_or_file).ExtractFileName();
     CHECK(PathService::Get(chrome::DIR_CHROMEOS_WALLPAPER_THUMBNAILS,
diff --git a/chrome/browser/chromeos/extensions/wallpaper_private_api_unittest.cc b/chrome/browser/chromeos/extensions/wallpaper_private_api_unittest.cc
index 4b54e8f..3388d69 100644
--- a/chrome/browser/chromeos/extensions/wallpaper_private_api_unittest.cc
+++ b/chrome/browser/chromeos/extensions/wallpaper_private_api_unittest.cc
@@ -11,6 +11,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/chromeos/extensions/wallpaper_private_api.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/ui/ash/multi_user/multi_user_window_manager.h"
 #include "chrome/browser/ui/ash/multi_user/multi_user_window_manager_chromeos.h"
 #include "ui/aura/test/test_windows.h"
diff --git a/chrome/browser/chromeos/file_manager/external_filesystem_apitest.cc b/chrome/browser/chromeos/file_manager/external_filesystem_apitest.cc
index 87a2ade..ecdfb71 100644
--- a/chrome/browser/chromeos/file_manager/external_filesystem_apitest.cc
+++ b/chrome/browser/chromeos/file_manager/external_filesystem_apitest.cc
@@ -11,7 +11,6 @@
 #include "chrome/browser/chromeos/drive/drive_integration_service.h"
 #include "chrome/browser/chromeos/file_manager/drive_test_util.h"
 #include "chrome/browser/chromeos/file_manager/volume_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/drive/fake_drive_service.h"
 #include "chrome/browser/extensions/extension_apitest.h"
@@ -20,6 +19,7 @@
 #include "chrome/browser/ui/browser.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_paths.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/test/test_utils.h"
@@ -511,9 +511,8 @@ class MultiProfileDriveFileSystemExtensionApiTest :
   virtual void SetUpOnMainThread() OVERRIDE {
     base::FilePath user_data_directory;
     PathService::Get(chrome::DIR_USER_DATA, &user_data_directory);
-    chromeos::UserManager::Get()->UserLoggedIn(kSecondProfileAccount,
-                                               kSecondProfileHash,
-                                               false);
+    user_manager::UserManager::Get()->UserLoggedIn(
+        kSecondProfileAccount, kSecondProfileHash, false);
     // Set up the secondary profile.
     base::FilePath profile_dir =
         user_data_directory.Append(
diff --git a/chrome/browser/chromeos/file_manager/file_manager_browsertest.cc b/chrome/browser/chromeos/file_manager/file_manager_browsertest.cc
index 6e83da8..31c1c38 100644
--- a/chrome/browser/chromeos/file_manager/file_manager_browsertest.cc
+++ b/chrome/browser/chromeos/file_manager/file_manager_browsertest.cc
@@ -29,7 +29,6 @@
 #include "chrome/browser/chromeos/file_manager/drive_test_util.h"
 #include "chrome/browser/chromeos/file_manager/path_util.h"
 #include "chrome/browser/chromeos/file_manager/volume_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/drive/fake_drive_service.h"
 #include "chrome/browser/extensions/component_loader.h"
@@ -41,6 +40,7 @@
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/chromeos_switches.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/test/test_utils.h"
 #include "extensions/browser/api/test/test_api.h"
@@ -1131,7 +1131,8 @@ class MultiProfileFileManagerBrowserTest : public FileManagerBrowserTestBase {
 
   // Adds a new user for testing to the current session.
   void AddUser(const TestAccountInfo& info, bool log_in) {
-    chromeos::UserManager* const user_manager = chromeos::UserManager::Get();
+    user_manager::UserManager* const user_manager =
+        user_manager::UserManager::Get();
     if (log_in)
       user_manager->UserLoggedIn(info.email, info.hash, false);
     user_manager->SaveUserDisplayName(info.email,
diff --git a/chrome/browser/chromeos/file_manager/file_tasks_unittest.cc b/chrome/browser/chromeos/file_manager/file_tasks_unittest.cc
index bd07eaf..21be58d 100644
--- a/chrome/browser/chromeos/file_manager/file_tasks_unittest.cc
+++ b/chrome/browser/chromeos/file_manager/file_tasks_unittest.cc
@@ -13,7 +13,7 @@
 #include "base/values.h"
 #include "chrome/browser/chromeos/drive/file_system_util.h"
 #include "chrome/browser/chromeos/file_manager/app_id.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #include "chrome/browser/drive/drive_app_registry.h"
diff --git a/chrome/browser/chromeos/file_manager/path_util.cc b/chrome/browser/chromeos/file_manager/path_util.cc
index 8896bfe..cf9b0ed 100644
--- a/chrome/browser/chromeos/file_manager/path_util.cc
+++ b/chrome/browser/chromeos/file_manager/path_util.cc
@@ -8,11 +8,11 @@
 #include "base/logging.h"
 #include "base/sys_info.h"
 #include "chrome/browser/chromeos/drive/file_system_util.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/download/download_prefs.h"
 #include "chrome/browser/profiles/profile.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "net/base/escape.h"
 
 namespace file_manager {
@@ -35,12 +35,12 @@ base::FilePath GetDownloadsFolderForProfile(Profile* profile) {
   // On non-ChromeOS system (test+development), the primary profile uses
   // $HOME/Downloads for ease for accessing local files for debugging.
   if (!base::SysInfo::IsRunningOnChromeOS() &&
-      chromeos::UserManager::IsInitialized()) {
+      user_manager::UserManager::IsInitialized()) {
     const user_manager::User* const user =
         chromeos::ProfileHelper::Get()->GetUserByProfile(
             profile->GetOriginalProfile());
     const user_manager::User* const primary_user =
-        chromeos::UserManager::Get()->GetPrimaryUser();
+        user_manager::UserManager::Get()->GetPrimaryUser();
     if (user == primary_user)
       return DownloadPrefs::GetDefaultDownloadDirectory();
   }
@@ -76,7 +76,7 @@ bool MigratePathFromOldFormat(Profile* profile,
   // no-op when multi-profile is enabled. This is necessary for (1) back
   // migration when multi-profile flag is enabled and then disabled, or (2) in
   // some edge cases (crbug.com/356322) that u-<hash> path is temporarily used.
-  if (chromeos::UserManager::IsInitialized()) {
+  if (user_manager::UserManager::IsInitialized()) {
     const user_manager::User* const user =
         chromeos::ProfileHelper::Get()->GetUserByProfile(profile);
     if (user) {
@@ -107,7 +107,7 @@ std::string GetDownloadsMountPointName(Profile* profile) {
   // are not associated with an user account. In that case, no suffix is added
   // because such a profile never belongs to a multi-profile session.
   user_manager::User* const user =
-      chromeos::UserManager::IsInitialized()
+      user_manager::UserManager::IsInitialized()
           ? chromeos::ProfileHelper::Get()->GetUserByProfile(
                 profile->GetOriginalProfile())
           : NULL;
diff --git a/chrome/browser/chromeos/file_system_provider/mount_path_util.cc b/chrome/browser/chromeos/file_system_provider/mount_path_util.cc
index 0456a7e..19283e4 100644
--- a/chrome/browser/chromeos/file_system_provider/mount_path_util.cc
+++ b/chrome/browser/chromeos/file_system_provider/mount_path_util.cc
@@ -11,11 +11,11 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/file_system_provider/provided_file_system.h"
 #include "chrome/browser/chromeos/file_system_provider/service.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 
 using content::BrowserThread;
@@ -51,7 +51,7 @@ base::FilePath GetMountPath(Profile* profile,
                             const std::string& extension_id,
                             const std::string& file_system_id) {
   user_manager::User* const user =
-      chromeos::UserManager::IsInitialized()
+      user_manager::UserManager::IsInitialized()
           ? chromeos::ProfileHelper::Get()->GetUserByProfile(
                 profile->GetOriginalProfile())
           : NULL;
diff --git a/chrome/browser/chromeos/file_system_provider/mount_path_util_unittest.cc b/chrome/browser/chromeos/file_system_provider/mount_path_util_unittest.cc
index d3d7df4..788eeab 100644
--- a/chrome/browser/chromeos/file_system_provider/mount_path_util_unittest.cc
+++ b/chrome/browser/chromeos/file_system_provider/mount_path_util_unittest.cc
@@ -13,6 +13,7 @@
 #include "chrome/browser/chromeos/file_system_provider/service.h"
 #include "chrome/browser/chromeos/file_system_provider/service_factory.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/test/base/testing_browser_process.h"
 #include "chrome/test/base/testing_profile.h"
diff --git a/chrome/browser/chromeos/file_system_provider/service_unittest.cc b/chrome/browser/chromeos/file_system_provider/service_unittest.cc
index ef99385..7a6d1e6 100644
--- a/chrome/browser/chromeos/file_system_provider/service_unittest.cc
+++ b/chrome/browser/chromeos/file_system_provider/service_unittest.cc
@@ -16,6 +16,7 @@
 #include "chrome/browser/chromeos/file_system_provider/observer.h"
 #include "chrome/browser/chromeos/file_system_provider/provided_file_system_info.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_pref_service_syncable.h"
 #include "chrome/test/base/testing_profile.h"
diff --git a/chrome/browser/chromeos/first_run/drive_first_run_controller.cc b/chrome/browser/chromeos/first_run/drive_first_run_controller.cc
index 09973a6..c69b2ed 100644
--- a/chrome/browser/chromeos/first_run/drive_first_run_controller.cc
+++ b/chrome/browser/chromeos/first_run/drive_first_run_controller.cc
@@ -14,7 +14,6 @@
 #include "chrome/browser/background/background_contents_service.h"
 #include "chrome/browser/background/background_contents_service_factory.h"
 #include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/extensions/chrome_extension_web_contents_observer.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/tab_contents/background_contents.h"
@@ -24,6 +23,7 @@
 #include "chrome/browser/ui/singleton_tabs.h"
 #include "chrome/grit/generated_resources.h"
 #include "chrome/grit/theme_resources.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/notification_details.h"
@@ -364,7 +364,7 @@ void DriveFirstRunController::EnableOfflineMode() {
     return;
   }
 
-  if (!UserManager::Get()->IsLoggedInAsRegularUser()) {
+  if (!user_manager::UserManager::Get()->IsLoggedInAsRegularUser()) {
     LOG(ERROR) << "Attempting to enable offline access "
                   "but not logged in a regular user.";
     OnOfflineInit(false, OUTCOME_WRONG_USER_TYPE);
diff --git a/chrome/browser/chromeos/first_run/first_run.cc b/chrome/browser/chromeos/first_run/first_run.cc
index c3e73e9..bf2d007 100644
--- a/chrome/browser/chromeos/first_run/first_run.cc
+++ b/chrome/browser/chromeos/first_run/first_run.cc
@@ -5,16 +5,18 @@
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
 #include "base/prefs/pref_service.h"
+#include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/first_run/first_run_controller.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/extension_service.h"
+#include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/ui/extensions/application_launch.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/chromeos_switches.h"
 #include "components/pref_registry/pref_registry_syncable.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/notification_service.h"
@@ -67,7 +69,7 @@ class DialogLauncher : public content::NotificationObserver {
     bool launched_in_test = command_line->HasSwitch(::switches::kTestType);
     bool launched_in_telemetry =
         command_line->HasSwitch(switches::kOobeSkipPostLogin);
-    bool is_user_new = chromeos::UserManager::Get()->IsCurrentUserNew();
+    bool is_user_new = user_manager::UserManager::Get()->IsCurrentUserNew();
     bool first_run_forced = command_line->HasSwitch(switches::kForceFirstRunUI);
     bool first_run_seen =
         profile_->GetPrefs()->GetBoolean(prefs::kFirstRunTutorialShown);
@@ -96,9 +98,8 @@ void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry) {
 }
 
 void MaybeLaunchDialogAfterSessionStart() {
-  UserManager* user_manager = UserManager::Get();
   new DialogLauncher(ProfileHelper::Get()->GetProfileByUserUnsafe(
-      user_manager->GetActiveUser()));
+      user_manager::UserManager::Get()->GetActiveUser()));
 }
 
 void LaunchTutorial() {
diff --git a/chrome/browser/chromeos/first_run/first_run_controller.cc b/chrome/browser/chromeos/first_run/first_run_controller.cc
index 8a8cd4fb..02b8cf1 100644
--- a/chrome/browser/chromeos/first_run/first_run_controller.cc
+++ b/chrome/browser/chromeos/first_run/first_run_controller.cc
@@ -13,9 +13,9 @@
 #include "chrome/browser/chromeos/first_run/steps/app_list_step.h"
 #include "chrome/browser/chromeos/first_run/steps/help_step.h"
 #include "chrome/browser/chromeos/first_run/steps/tray_step.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/ui/chrome_pages.h"
+#include "components/user_manager/user_manager.h"
 #include "ui/views/widget/widget.h"
 
 namespace {
@@ -71,7 +71,7 @@ FirstRunController::FirstRunController()
 
 void FirstRunController::Init() {
   start_time_ = base::Time::Now();
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   user_profile_ = ProfileHelper::Get()->GetProfileByUserUnsafe(
       user_manager->GetActiveUser());
 
diff --git a/chrome/browser/chromeos/input_method/input_method_manager_impl.cc b/chrome/browser/chromeos/input_method/input_method_manager_impl.cc
index 39d4a70..87518b9 100644
--- a/chrome/browser/chromeos/input_method/input_method_manager_impl.cc
+++ b/chrome/browser/chromeos/input_method/input_method_manager_impl.cc
@@ -22,7 +22,6 @@
 #include "chrome/browser/chromeos/input_method/component_extension_ime_manager_impl.h"
 #include "chrome/browser/chromeos/input_method/input_method_engine.h"
 #include "chrome/browser/chromeos/language_preferences.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/ime/component_extension_ime_manager.h"
diff --git a/chrome/browser/chromeos/input_method/input_method_persistence.cc b/chrome/browser/chromeos/input_method/input_method_persistence.cc
index c0c82fb..e9a2cd9 100644
--- a/chrome/browser/chromeos/input_method/input_method_persistence.cc
+++ b/chrome/browser/chromeos/input_method/input_method_persistence.cc
@@ -11,7 +11,6 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/input_method/input_method_util.h"
 #include "chrome/browser/chromeos/language_preferences.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/pref_names.h"
diff --git a/chrome/browser/chromeos/kiosk_mode/kiosk_mode_idle_logout.cc b/chrome/browser/chromeos/kiosk_mode/kiosk_mode_idle_logout.cc
index 2ca6103..1c2c241 100644
--- a/chrome/browser/chromeos/kiosk_mode/kiosk_mode_idle_logout.cc
+++ b/chrome/browser/chromeos/kiosk_mode/kiosk_mode_idle_logout.cc
@@ -11,8 +11,8 @@
 #include "base/message_loop/message_loop.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/kiosk_mode/kiosk_mode_settings.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/ui/idle_logout_dialog_view.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/notification_service.h"
@@ -48,7 +48,7 @@ KioskModeIdleLogout::~KioskModeIdleLogout() {
 }
 
 void KioskModeIdleLogout::Setup() {
-  if (UserManager::Get()->IsLoggedInAsDemoUser()) {
+  if (user_manager::UserManager::Get()->IsLoggedInAsDemoUser()) {
     // This means that we're recovering from a crash.  The user is already
     // logged in, so go ahead and start the timer.
     Start();
diff --git a/chrome/browser/chromeos/kiosk_mode/kiosk_mode_idle_logout_unittest.cc b/chrome/browser/chromeos/kiosk_mode/kiosk_mode_idle_logout_unittest.cc
index e260cde..8843dca 100644
--- a/chrome/browser/chromeos/kiosk_mode/kiosk_mode_idle_logout_unittest.cc
+++ b/chrome/browser/chromeos/kiosk_mode/kiosk_mode_idle_logout_unittest.cc
@@ -11,8 +11,8 @@
 #include "base/message_loop/message_loop.h"
 #include "base/synchronization/waitable_event.h"
 #include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/settings/device_settings_test_helper.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/notification_service.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -64,7 +64,8 @@ TEST_F(KioskModeIdleLogoutTest, DISABLED_CheckObserversBeforeUserLogin) {
 TEST_F(KioskModeIdleLogoutTest, DISABLED_CheckObserversAfterUserLogin) {
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_LOGIN_USER_CHANGED,
-      content::Source<UserManager>(UserManager::Get()),
+      content::Source<user_manager::UserManager>(
+          user_manager::UserManager::Get()),
       // Ideally this should be the user logged in, but since we won't really be
       // checking for the current logged in user in our observer anyway, giving
       // NoDetails here is fine.
diff --git a/chrome/browser/chromeos/kiosk_mode/kiosk_mode_settings.cc b/chrome/browser/chromeos/kiosk_mode/kiosk_mode_settings.cc
index 22a0010..231403e 100644
--- a/chrome/browser/chromeos/kiosk_mode/kiosk_mode_settings.cc
+++ b/chrome/browser/chromeos/kiosk_mode/kiosk_mode_settings.cc
@@ -11,7 +11,6 @@
 #include "base/lazy_instance.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/kiosk_mode/kiosk_mode_screensaver.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
diff --git a/chrome/browser/chromeos/login/app_launch_controller.cc b/chrome/browser/chromeos/login/app_launch_controller.cc
index 3408b5c..99b7873 100644
--- a/chrome/browser/chromeos/login/app_launch_controller.cc
+++ b/chrome/browser/chromeos/login/app_launch_controller.cc
@@ -31,6 +31,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/webui/chromeos/login/app_launch_splash_screen_handler.h"
 #include "chrome/browser/ui/webui/chromeos/login/oobe_ui.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "net/base/network_change_notifier.h"
 
@@ -296,7 +297,7 @@ bool AppLaunchController::CanConfigureNetwork() {
     return true;
   }
 
-  return !UserManager::Get()->GetOwnerEmail().empty();
+  return !user_manager::UserManager::Get()->GetOwnerEmail().empty();
 }
 
 bool AppLaunchController::NeedOwnerAuthToConfigureNetwork() {
diff --git a/chrome/browser/chromeos/login/app_launch_signin_screen.cc b/chrome/browser/chromeos/login/app_launch_signin_screen.cc
index ee18fe7..de79951 100644
--- a/chrome/browser/chromeos/login/app_launch_signin_screen.cc
+++ b/chrome/browser/chromeos/login/app_launch_signin_screen.cc
@@ -11,13 +11,14 @@
 #include "chrome/browser/signin/screenlock_bridge.h"
 #include "chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h"
 #include "chrome/grit/generated_resources.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/web_ui.h"
 #include "ui/base/l10n/l10n_util.h"
 
 namespace chromeos {
 
-UserManager* AppLaunchSigninScreen::test_user_manager_ = NULL;
+user_manager::UserManager* AppLaunchSigninScreen::test_user_manager_ = NULL;
 
 AppLaunchSigninScreen::AppLaunchSigninScreen(
     OobeUI* oobe_ui, Delegate* delegate)
@@ -39,7 +40,7 @@ void AppLaunchSigninScreen::Show() {
 }
 
 void AppLaunchSigninScreen::InitOwnerUserList() {
-  UserManager* user_manager = GetUserManager();
+  user_manager::UserManager* user_manager = GetUserManager();
   const std::string& owner_email = user_manager->GetOwnerEmail();
   const user_manager::UserList& all_users = user_manager->GetUsers();
 
@@ -57,12 +58,13 @@ void AppLaunchSigninScreen::InitOwnerUserList() {
 
 // static
 void AppLaunchSigninScreen::SetUserManagerForTesting(
-    UserManager* user_manager) {
+    user_manager::UserManager* user_manager) {
   test_user_manager_ = user_manager;
 }
 
-UserManager* AppLaunchSigninScreen::GetUserManager() {
-  return test_user_manager_ ? test_user_manager_ : UserManager::Get();
+user_manager::UserManager* AppLaunchSigninScreen::GetUserManager() {
+  return test_user_manager_ ? test_user_manager_
+                            : user_manager::UserManager::Get();
 }
 
 void AppLaunchSigninScreen::CancelPasswordChangedFlow() {
diff --git a/chrome/browser/chromeos/login/app_launch_signin_screen.h b/chrome/browser/chromeos/login/app_launch_signin_screen.h
index 665eddd..2fbcf66 100644
--- a/chrome/browser/chromeos/login/app_launch_signin_screen.h
+++ b/chrome/browser/chromeos/login/app_launch_signin_screen.h
@@ -8,12 +8,12 @@
 #include <string>
 
 #include "base/memory/ref_counted.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/signin/screenlock_bridge.h"
 #include "chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h"
 #include "chromeos/login/auth/auth_status_consumer.h"
 #include "chromeos/login/auth/authenticator.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 
 namespace chromeos {
 
@@ -43,11 +43,11 @@ class AppLaunchSigninScreen : public SigninScreenHandlerDelegate,
 
   void Show();
 
-  static void SetUserManagerForTesting(UserManager* user_manager);
+  static void SetUserManagerForTesting(user_manager::UserManager* user_manager);
 
  private:
   void InitOwnerUserList();
-  UserManager* GetUserManager();
+  user_manager::UserManager* GetUserManager();
 
   // SigninScreenHandlerDelegate implementation:
   virtual void CancelPasswordChangedFlow() OVERRIDE;
@@ -96,7 +96,7 @@ class AppLaunchSigninScreen : public SigninScreenHandlerDelegate,
   // This list should have at most one user, and that user should be the owner.
   user_manager::UserList owner_user_list_;
 
-  static UserManager* test_user_manager_;
+  static user_manager::UserManager* test_user_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(AppLaunchSigninScreen);
 };
diff --git a/chrome/browser/chromeos/login/auth/login_performer.cc b/chrome/browser/chromeos/login/auth/login_performer.cc
index ec9c19f..b093664 100644
--- a/chrome/browser/chromeos/login/auth/login_performer.cc
+++ b/chrome/browser/chromeos/login/auth/login_performer.cc
@@ -18,8 +18,8 @@
 #include "chrome/browser/chromeos/login/supervised/supervised_user_authentication.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_constants.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_login_flow.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_local_account_policy_service.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
@@ -29,6 +29,7 @@
 #include "chromeos/dbus/session_manager_client.h"
 #include "chromeos/login/user_names.h"
 #include "chromeos/settings/cros_settings_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
@@ -219,7 +220,7 @@ void LoginPerformer::LoginAsSupervisedUser(
     return;
   }
 
-  if (!UserManager::Get()->AreSupervisedUsersAllowed()) {
+  if (!user_manager::UserManager::Get()->AreSupervisedUsersAllowed()) {
     LOG(ERROR) << "Login attempt of supervised user detected.";
     delegate_->WhiteListCheckFailed(user_context.GetUserID());
     return;
@@ -228,11 +229,11 @@ void LoginPerformer::LoginAsSupervisedUser(
   SupervisedUserLoginFlow* new_flow =
       new SupervisedUserLoginFlow(user_context.GetUserID());
   new_flow->set_host(
-      UserManager::Get()->GetUserFlow(user_context.GetUserID())->host());
-  UserManager::Get()->SetUserFlow(user_context.GetUserID(), new_flow);
+      ChromeUserManager::Get()->GetUserFlow(user_context.GetUserID())->host());
+  ChromeUserManager::Get()->SetUserFlow(user_context.GetUserID(), new_flow);
 
-  SupervisedUserAuthentication* authentication = UserManager::Get()->
-      GetSupervisedUserManager()->GetAuthentication();
+  SupervisedUserAuthentication* authentication =
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
 
   UserContext user_context_copy = authentication->TransformKey(user_context);
 
diff --git a/chrome/browser/chromeos/login/auth/mount_manager.cc b/chrome/browser/chromeos/login/auth/mount_manager.cc
index f0b3479..5ca790c 100644
--- a/chrome/browser/chromeos/login/auth/mount_manager.cc
+++ b/chrome/browser/chromeos/login/auth/mount_manager.cc
@@ -4,7 +4,6 @@
 
 #include "chrome/browser/chromeos/login/auth/mount_manager.h"
 
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 
 namespace chromeos {
diff --git a/chrome/browser/chromeos/login/auth/parallel_authenticator.cc b/chrome/browser/chromeos/login/auth/parallel_authenticator.cc
index 66495ed..f9ca2d3 100644
--- a/chrome/browser/chromeos/login/auth/parallel_authenticator.cc
+++ b/chrome/browser/chromeos/login/auth/parallel_authenticator.cc
@@ -11,7 +11,6 @@
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/boot_times_loader.h"
 #include "chrome/browser/chromeos/login/auth/authentication_notification_details.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service_factory.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
@@ -25,6 +24,7 @@
 #include "chromeos/login/auth/user_context.h"
 #include "chromeos/login/login_state.h"
 #include "chromeos/login/user_names.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
@@ -242,12 +242,13 @@ void ParallelAuthenticator::AuthenticateToLogin(
     Profile* profile,
     const UserContext& user_context) {
   authentication_profile_ = profile;
-  current_state_.reset(new AuthAttemptState(
-      user_context,
-      user_manager::USER_TYPE_REGULAR,
-      false,  // unlock
-      false,  // online_complete
-      !UserManager::Get()->IsKnownUser(user_context.GetUserID())));
+  current_state_.reset(
+      new AuthAttemptState(user_context,
+                           user_manager::USER_TYPE_REGULAR,
+                           false,  // unlock
+                           false,  // online_complete
+                           !user_manager::UserManager::Get()->IsKnownUser(
+                               user_context.GetUserID())));
   // Reset the verified flag.
   owner_is_verified_ = false;
 
@@ -261,12 +262,13 @@ void ParallelAuthenticator::AuthenticateToLogin(
 void ParallelAuthenticator::CompleteLogin(Profile* profile,
                                           const UserContext& user_context) {
   authentication_profile_ = profile;
-  current_state_.reset(new AuthAttemptState(
-      user_context,
-      user_manager::USER_TYPE_REGULAR,
-      true,   // unlock
-      false,  // online_complete
-      !UserManager::Get()->IsKnownUser(user_context.GetUserID())));
+  current_state_.reset(
+      new AuthAttemptState(user_context,
+                           user_manager::USER_TYPE_REGULAR,
+                           true,   // unlock
+                           false,  // online_complete
+                           !user_manager::UserManager::Get()->IsKnownUser(
+                               user_context.GetUserID())));
 
   // Reset the verified flag.
   owner_is_verified_ = false;
diff --git a/chrome/browser/chromeos/login/auth/parallel_authenticator_unittest.cc b/chrome/browser/chromeos/login/auth/parallel_authenticator_unittest.cc
index 248defa..8d3b03e 100644
--- a/chrome/browser/chromeos/login/auth/parallel_authenticator_unittest.cc
+++ b/chrome/browser/chromeos/login/auth/parallel_authenticator_unittest.cc
@@ -15,7 +15,7 @@
 #include "base/strings/stringprintf.h"
 #include "chrome/browser/chromeos/login/auth/mock_url_fetchers.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service_factory.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
@@ -35,7 +35,6 @@
 #include "chromeos/login/auth/mock_auth_status_consumer.h"
 #include "chromeos/login/auth/test_attempt_state.h"
 #include "chromeos/login/auth/user_context.h"
-#include "components/user_manager/user.h"
 #include "content/public/test/test_browser_thread_bundle.h"
 #include "crypto/nss_util_internal.h"
 #include "crypto/scoped_test_nss_chromeos_user.h"
diff --git a/chrome/browser/chromeos/login/chrome_restart_request.cc b/chrome/browser/chromeos/login/chrome_restart_request.cc
index 9461bd1..c02904b 100644
--- a/chrome/browser/chromeos/login/chrome_restart_request.cc
+++ b/chrome/browser/chromeos/login/chrome_restart_request.cc
@@ -22,7 +22,6 @@
 #include "cc/base/switches.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/boot_times_loader.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_paths.h"
diff --git a/chrome/browser/chromeos/login/crash_restore_browsertest.cc b/chrome/browser/chromeos/login/crash_restore_browsertest.cc
index a5fa609..f5ce615 100644
--- a/chrome/browser/chromeos/login/crash_restore_browsertest.cc
+++ b/chrome/browser/chromeos/login/crash_restore_browsertest.cc
@@ -9,7 +9,6 @@
 #include "base/memory/ref_counted.h"
 #include "base/run_loop.h"
 #include "chrome/browser/chromeos/login/session/user_session_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/dbus/cryptohome_client.h"
@@ -17,6 +16,7 @@
 #include "chromeos/dbus/fake_session_manager_client.h"
 #include "chromeos/dbus/session_manager_client.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/test/test_utils.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
@@ -59,7 +59,7 @@ class CrashRestoreSimpleTest : public InProcessBrowserTest {
 };
 
 IN_PROC_BROWSER_TEST_F(CrashRestoreSimpleTest, RestoreSessionForOneUser) {
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   user_manager::User* user = user_manager->GetActiveUser();
   ASSERT_TRUE(user);
   EXPECT_EQ(kUserId1, user->email());
@@ -132,7 +132,7 @@ IN_PROC_BROWSER_TEST_F(CrashRestoreComplexTest, RestoreSessionForThreeUsers) {
 
   // User that is last in the user sessions map becomes active. This behavior
   // will become better defined once each user gets a separate user desktop.
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   user_manager::User* user = user_manager->GetActiveUser();
   ASSERT_TRUE(user);
   EXPECT_EQ(kUserId3, user->email());
diff --git a/chrome/browser/chromeos/login/demo_mode/demo_app_launcher.cc b/chrome/browser/chromeos/login/demo_mode/demo_app_launcher.cc
index 9e87fb5..466638f 100644
--- a/chrome/browser/chromeos/login/demo_mode/demo_app_launcher.cc
+++ b/chrome/browser/chromeos/login/demo_mode/demo_app_launcher.cc
@@ -10,7 +10,6 @@
 #include "chrome/browser/chromeos/app_mode/app_session_lifetime.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/extensions/component_loader.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
@@ -21,6 +20,7 @@
 #include "chrome/grit/browser_resources.h"
 #include "chromeos/network/network_handler.h"
 #include "chromeos/network/network_state_handler.h"
+#include "components/user_manager/user_manager.h"
 #include "extensions/browser/extension_system.h"
 #include "extensions/common/extension.h"
 #include "ui/base/window_open_disposition.h"
@@ -96,7 +96,7 @@ void DemoAppLauncher::OnProfileLoaded(Profile* profile) {
       profile, extension, extensions::LAUNCH_CONTAINER_WINDOW, NEW_WINDOW));
   InitAppSession(profile, extension_id);
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   LoginDisplayHostImpl::default_host()->Finalize();
 }
diff --git a/chrome/browser/chromeos/login/demo_mode/demo_app_launcher_browsertest.cc b/chrome/browser/chromeos/login/demo_mode/demo_app_launcher_browsertest.cc
index 35f988b..c65f0cf 100644
--- a/chrome/browser/chromeos/login/demo_mode/demo_app_launcher_browsertest.cc
+++ b/chrome/browser/chromeos/login/demo_mode/demo_app_launcher_browsertest.cc
@@ -11,7 +11,6 @@
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/demo_mode/demo_app_launcher.h"
 #include "chrome/browser/chromeos/login/test/app_window_waiter.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/extensions/extension_browsertest.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
@@ -19,6 +18,7 @@
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/network/network_state.h"
 #include "chromeos/network/network_state_handler.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_source.h"
 #include "content/public/test/test_utils.h"
@@ -35,7 +35,7 @@ base::FilePath GetTestDemoAppPath() {
 }
 
 Profile* WaitForProfile() {
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (!user_manager || !user_manager->IsUserLoggedIn()) {
     content::WindowedNotificationObserver(
         chrome::NOTIFICATION_SESSION_STARTED,
diff --git a/chrome/browser/chromeos/login/existing_user_controller.cc b/chrome/browser/chromeos/login/existing_user_controller.cc
index ff25f97..0030ed7 100644
--- a/chrome/browser/chromeos/login/existing_user_controller.cc
+++ b/chrome/browser/chromeos/login/existing_user_controller.cc
@@ -33,7 +33,8 @@
 #include "chrome/browser/chromeos/login/login_utils.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/user_flow.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_local_account.h"
@@ -60,6 +61,7 @@
 #include "components/policy/core/common/policy_map.h"
 #include "components/policy/core/common/policy_service.h"
 #include "components/policy/core/common/policy_types.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
@@ -211,7 +213,7 @@ void ExistingUserController::UpdateLoginDisplay(
     // TODO(xiyuan): Clean user profile whose email is not in whitelist.
     bool meets_supervised_requirements =
         (*it)->GetType() != user_manager::USER_TYPE_SUPERVISED ||
-        UserManager::Get()->AreSupervisedUsersAllowed();
+        user_manager::UserManager::Get()->AreSupervisedUsersAllowed();
     bool meets_whitelist_requirements =
         LoginUtils::IsWhitelisted((*it)->email(), NULL) ||
         (*it)->GetType() != user_manager::USER_TYPE_REGULAR;
@@ -444,8 +446,8 @@ void ExistingUserController::Login(const UserContext& user_context,
 void ExistingUserController::PerformLogin(
     const UserContext& user_context,
     LoginPerformer::AuthorizationMode auth_mode) {
-  UserManager::Get()->GetUserFlow(last_login_attempt_username_)->
-      set_host(host_);
+  ChromeUserManager::Get()->GetUserFlow(last_login_attempt_username_)->set_host(
+      host_);
 
   BootTimesLoader::Get()->RecordLoginAttempted();
 
@@ -490,8 +492,10 @@ void ExistingUserController::LoginAsRetailModeUser() {
 }
 
 void ExistingUserController::LoginAsGuest() {
-  if (is_login_in_progress_ || UserManager::Get()->IsUserLoggedIn())
+  if (is_login_in_progress_ ||
+      user_manager::UserManager::Get()->IsUserLoggedIn()) {
     return;
+  }
 
   // Stop the auto-login timer when attempting login.
   StopPublicSessionAutoLoginTimer();
@@ -550,8 +554,10 @@ void ExistingUserController::MigrateUserData(const std::string& old_password) {
 
 void ExistingUserController::LoginAsPublicSession(
     const UserContext& user_context) {
-  if (is_login_in_progress_ || UserManager::Get()->IsUserLoggedIn())
+  if (is_login_in_progress_ ||
+      user_manager::UserManager::Get()->IsUserLoggedIn()) {
     return;
+  }
 
   // Stop the auto-login timer when attempting login.
   StopPublicSessionAutoLoginTimer();
@@ -582,7 +588,7 @@ void ExistingUserController::LoginAsPublicSession(
   // If there is no public account with the given user ID, logging in is not
   // possible.
   const user_manager::User* user =
-      UserManager::Get()->FindUser(user_context.GetUserID());
+      user_manager::UserManager::Get()->FindUser(user_context.GetUserID());
   if (!user || user->GetType() != user_manager::USER_TYPE_PUBLIC_ACCOUNT) {
     // Re-enable clicking on other windows.
     login_display_->SetUIEnabled(true);
@@ -767,8 +773,9 @@ void ExistingUserController::OnAuthFailure(const AuthFailure& failure) {
   guest_mode_url_ = GURL::EmptyGURL();
   std::string error = failure.GetErrorString();
 
-  if (UserManager::Get()->GetUserFlow(last_login_attempt_username_)->
-          HandleLoginFailure(failure)) {
+  if (ChromeUserManager::Get()
+          ->GetUserFlow(last_login_attempt_username_)
+          ->HandleLoginFailure(failure)) {
     login_display_->SetUIEnabled(true);
     return;
   }
@@ -788,8 +795,8 @@ void ExistingUserController::OnAuthFailure(const AuthFailure& failure) {
   } else {
     // Check networking after trying to login in case user is
     // cached locally or the local admin account.
-    bool is_known_user =
-        UserManager::Get()->IsKnownUser(last_login_attempt_username_);
+    bool is_known_user = user_manager::UserManager::Get()->IsKnownUser(
+        last_login_attempt_username_);
     if (!network_state_helper_->IsConnected()) {
       if (is_known_user)
         ShowError(IDS_LOGIN_ERROR_AUTHENTICATING, error);
@@ -816,7 +823,7 @@ void ExistingUserController::OnAuthFailure(const AuthFailure& failure) {
 
   // Reset user flow to default, so that special flow will not affect next
   // attempt.
-  UserManager::Get()->ResetUserFlow(last_login_attempt_username_);
+  ChromeUserManager::Get()->ResetUserFlow(last_login_attempt_username_);
 
   if (auth_status_consumer_)
     auth_status_consumer_->OnAuthFailure(failure);
@@ -835,8 +842,9 @@ void ExistingUserController::OnAuthSuccess(const UserContext& user_context) {
   password_changed_ = login_performer_->password_changed();
   auth_mode_ = login_performer_->auth_mode();
 
-  UserManager::Get()->GetUserFlow(user_context.GetUserID())->
-      HandleLoginSuccess(user_context);
+  ChromeUserManager::Get()
+      ->GetUserFlow(user_context.GetUserID())
+      ->HandleLoginSuccess(user_context);
 
   StopPublicSessionAutoLoginTimer();
 
@@ -854,8 +862,8 @@ void ExistingUserController::OnAuthSuccess(const UserContext& user_context) {
 
   // Update user's displayed email.
   if (!display_email_.empty()) {
-    UserManager::Get()->SaveUserDisplayEmail(user_context.GetUserID(),
-                                             display_email_);
+    user_manager::UserManager::Get()->SaveUserDisplayEmail(
+        user_context.GetUserID(), display_email_);
     display_email_.clear();
   }
 
@@ -870,7 +878,7 @@ void ExistingUserController::OnProfilePrepared(Profile* profile) {
   // Reenable clicking on other windows and status area.
   login_display_->SetUIEnabled(true);
 
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (user_manager->IsCurrentUserNew() &&
       user_manager->IsLoggedInAsSupervisedUser()) {
     // Supervised users should launch into empty desktop on first run.
@@ -878,7 +886,9 @@ void ExistingUserController::OnProfilePrepared(Profile* profile) {
   }
 
   if (user_manager->IsCurrentUserNew() &&
-      !user_manager->GetCurrentUserFlow()->ShouldSkipPostLoginScreens() &&
+      !ChromeUserManager::Get()
+           ->GetCurrentUserFlow()
+           ->ShouldSkipPostLoginScreens() &&
       !WizardController::default_controller()->skip_post_login_screens()) {
     // Don't specify start URLs if the administrator has configured the start
     // URLs via policy.
@@ -933,8 +943,9 @@ void ExistingUserController::OnPasswordChangeDetected() {
     return;
   }
 
-  if (UserManager::Get()->GetUserFlow(last_login_attempt_username_)->
-          HandlePasswordChangeDetected()) {
+  if (ChromeUserManager::Get()
+          ->GetUserFlow(last_login_attempt_username_)
+          ->HandlePasswordChangeDetected()) {
     return;
   }
 
@@ -1005,7 +1016,7 @@ void ExistingUserController::OnOnlineChecked(const std::string& username,
 void ExistingUserController::DeviceSettingsChanged() {
   if (host_ != NULL) {
     // Signed settings or user list changed. Notify views and update them.
-    UpdateLoginDisplay(chromeos::UserManager::Get()->GetUsers());
+    UpdateLoginDisplay(user_manager::UserManager::Get()->GetUsers());
     ConfigurePublicSessionAutoLogin();
     return;
   }
@@ -1047,8 +1058,8 @@ void ExistingUserController::ConfigurePublicSessionAutoLogin() {
     }
   }
 
-  const user_manager::User* user =
-      UserManager::Get()->FindUser(public_session_auto_login_username_);
+  const user_manager::User* user = user_manager::UserManager::Get()->FindUser(
+      public_session_auto_login_username_);
   if (!user || user->GetType() != user_manager::USER_TYPE_PUBLIC_ACCOUNT)
     public_session_auto_login_username_.clear();
 
@@ -1114,7 +1125,7 @@ void ExistingUserController::InitializeStartUrls() const {
   std::vector<std::string> start_urls;
 
   const base::ListValue *urls;
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   bool can_show_getstarted_guide =
       user_manager->GetActiveUser()->GetType() ==
           user_manager::USER_TYPE_REGULAR &&
@@ -1189,7 +1200,8 @@ void ExistingUserController::ShowError(int error_id,
   if (error_id == IDS_LOGIN_ERROR_AUTHENTICATING) {
     if (num_login_attempts_ > 1) {
       const user_manager::User* user =
-          UserManager::Get()->FindUser(last_login_attempt_username_);
+          user_manager::UserManager::Get()->FindUser(
+              last_login_attempt_username_);
       if (user && (user->GetType() == user_manager::USER_TYPE_SUPERVISED))
         error_id = IDS_LOGIN_ERROR_AUTHENTICATING_2ND_TIME_SUPERVISED;
     }
@@ -1202,7 +1214,7 @@ void ExistingUserController::ShowGaiaPasswordChanged(
     const std::string& username) {
   // Invalidate OAuth token, since it can't be correct after password is
   // changed.
-  UserManager::Get()->SaveUserOAuthStatus(
+  user_manager::UserManager::Get()->SaveUserOAuthStatus(
       username, user_manager::User::OAUTH2_TOKEN_STATUS_INVALID);
 
   login_display_->SetUIEnabled(true);
diff --git a/chrome/browser/chromeos/login/existing_user_controller_auto_login_unittest.cc b/chrome/browser/chromeos/login/existing_user_controller_auto_login_unittest.cc
index 772d82f..50a3553 100644
--- a/chrome/browser/chromeos/login/existing_user_controller_auto_login_unittest.cc
+++ b/chrome/browser/chromeos/login/existing_user_controller_auto_login_unittest.cc
@@ -11,7 +11,7 @@
 #include "chrome/browser/chromeos/login/ui/mock_login_display.h"
 #include "chrome/browser/chromeos/login/ui/mock_login_display_host.h"
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/policy/device_local_account.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_test_helper.h"
diff --git a/chrome/browser/chromeos/login/existing_user_controller_browsertest.cc b/chrome/browser/chromeos/login/existing_user_controller_browsertest.cc
index 247b27e..0464c0d 100644
--- a/chrome/browser/chromeos/login/existing_user_controller_browsertest.cc
+++ b/chrome/browser/chromeos/login/existing_user_controller_browsertest.cc
@@ -19,7 +19,7 @@
 #include "chrome/browser/chromeos/login/ui/mock_login_display.h"
 #include "chrome/browser/chromeos/login/ui/mock_login_display_host.h"
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_local_account.h"
@@ -43,6 +43,7 @@
 #include "components/policy/core/common/cloud/mock_cloud_policy_store.h"
 #include "components/policy/core/common/cloud/policy_builder.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/test/mock_notification_observer.h"
 #include "content/public/test/test_utils.h"
@@ -350,11 +351,12 @@ class ExistingUserControllerPublicSessionTest
     ExistingUserControllerTest::SetUpOnMainThread();
 
     // Wait for the public session user to be created.
-    if (!chromeos::UserManager::Get()->IsKnownUser(public_session_user_id_)) {
+    if (!user_manager::UserManager::Get()->IsKnownUser(
+            public_session_user_id_)) {
       content::WindowedNotificationObserver(
           chrome::NOTIFICATION_USER_LIST_CHANGED,
-          base::Bind(&chromeos::UserManager::IsKnownUser,
-                     base::Unretained(chromeos::UserManager::Get()),
+          base::Bind(&user_manager::UserManager::IsKnownUser,
+                     base::Unretained(user_manager::UserManager::Get()),
                      public_session_user_id_)).Wait();
     }
 
diff --git a/chrome/browser/chromeos/login/fake_login_utils.cc b/chrome/browser/chromeos/login/fake_login_utils.cc
index 085d852..aa3c889 100644
--- a/chrome/browser/chromeos/login/fake_login_utils.cc
+++ b/chrome/browser/chromeos/login/fake_login_utils.cc
@@ -10,8 +10,8 @@
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host.h"
 #include "chrome/browser/chromeos/login/user_flow.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/first_run/first_run.h"
 #include "chrome/browser/profiles/profile.h"
@@ -21,6 +21,7 @@
 #include "chromeos/login/auth/mock_authenticator.h"
 #include "chromeos/login/auth/user_context.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -37,9 +38,8 @@ void FakeLoginUtils::RespectLocalePreference(Profile*,
 
 void FakeLoginUtils::DoBrowserLaunch(Profile* profile,
                                      LoginDisplayHost* login_host) {
-
-  if (!UserManager::Get()->GetCurrentUserFlow()->ShouldLaunchBrowser()) {
-      UserManager::Get()->GetCurrentUserFlow()->LaunchExtraSteps(profile);
+  if (!ChromeUserManager::Get()->GetCurrentUserFlow()->ShouldLaunchBrowser()) {
+    ChromeUserManager::Get()->GetCurrentUserFlow()->LaunchExtraSteps(profile);
       return;
   }
   login_host->BeforeSessionStart();
@@ -58,17 +58,18 @@ void FakeLoginUtils::DoBrowserLaunch(Profile* profile,
   }
   if (login_host)
     login_host->Finalize();
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 }
 
 void FakeLoginUtils::PrepareProfile(const UserContext& user_context,
                                     bool has_cookies,
                                     bool has_active_session,
                                     LoginUtils::Delegate* delegate) {
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       user_context.GetUserID(), user_context.GetUserIDHash(), false);
   user_manager::User* user =
-      UserManager::Get()->FindUserAndModify(user_context.GetUserID());
+      user_manager::UserManager::Get()->FindUserAndModify(
+          user_context.GetUserID());
   DCHECK(user);
 
   // Make sure that we get the real Profile instead of the login Profile.
@@ -77,11 +78,12 @@ void FakeLoginUtils::PrepareProfile(const UserContext& user_context,
   profile->GetPrefs()->SetString(prefs::kGoogleServicesUsername,
                                  user_context.GetUserID());
 
-  if (UserManager::Get()->IsLoggedInAsSupervisedUser()) {
-    user_manager::User* active_user = UserManager::Get()->GetActiveUser();
+  if (user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser()) {
+    user_manager::User* active_user =
+        user_manager::UserManager::Get()->GetActiveUser();
     std::string supervised_user_sync_id =
-        UserManager::Get()->GetSupervisedUserManager()->
-            GetUserSyncId(active_user->email());
+        ChromeUserManager::Get()->GetSupervisedUserManager()->GetUserSyncId(
+            active_user->email());
     if (supervised_user_sync_id.empty())
       supervised_user_sync_id = "DUMMY ID";
     profile->GetPrefs()->SetString(prefs::kSupervisedUserId,
diff --git a/chrome/browser/chromeos/login/helper.cc b/chrome/browser/chromeos/login/helper.cc
index f76d3c6..45aafe1 100644
--- a/chrome/browser/chromeos/login/helper.cc
+++ b/chrome/browser/chromeos/login/helper.cc
@@ -7,7 +7,6 @@
 #include "ash/shell.h"
 #include "base/command_line.h"
 #include "base/strings/utf_string_conversions.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/grit/generated_resources.h"
 #include "chrome/grit/theme_resources.h"
 #include "chromeos/chromeos_switches.h"
diff --git a/chrome/browser/chromeos/login/kiosk_browsertest.cc b/chrome/browser/chromeos/login/kiosk_browsertest.cc
index b7cb0430..e67f238 100644
--- a/chrome/browser/chromeos/login/kiosk_browsertest.cc
+++ b/chrome/browser/chromeos/login/kiosk_browsertest.cc
@@ -25,6 +25,7 @@
 #include "chrome/browser/chromeos/login/test/oobe_screen_waiter.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/policy/device_policy_cros_browser_test.h"
 #include "chrome/browser/chromeos/policy/proto/chrome_device_policy.pb.h"
diff --git a/chrome/browser/chromeos/login/lock/screen_locker.cc b/chrome/browser/chromeos/login/lock/screen_locker.cc
index fe389eb..3dd1dc8 100644
--- a/chrome/browser/chromeos/login/lock/screen_locker.cc
+++ b/chrome/browser/chromeos/login/lock/screen_locker.cc
@@ -30,8 +30,8 @@
 #include "chrome/browser/chromeos/login/login_utils.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_authentication.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/browser/signin/signin_manager_factory.h"
 #include "chrome/browser/ui/webui/chromeos/login/screenlock_icon_provider.h"
@@ -45,6 +45,7 @@
 #include "chromeos/login/auth/authenticator.h"
 #include "chromeos/login/auth/extended_authenticator.h"
 #include "components/signin/core/browser/signin_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
@@ -202,10 +203,11 @@ void ScreenLocker::OnAuthSuccess(const UserContext& user_context) {
   }
 
   const user_manager::User* user =
-      UserManager::Get()->FindUser(user_context.GetUserID());
+      user_manager::UserManager::Get()->FindUser(user_context.GetUserID());
   if (user) {
     if (!user->is_active())
-      UserManager::Get()->SwitchActiveUser(user_context.GetUserID());
+      user_manager::UserManager::Get()->SwitchActiveUser(
+          user_context.GetUserID());
   } else {
     NOTREACHED() << "Logged in user not found.";
   }
@@ -253,7 +255,7 @@ void ScreenLocker::Authenticate(const UserContext& user_context) {
   if (const user_manager::User* user =
           FindUnlockUser(user_context.GetUserID())) {
     if (user->GetType() == user_manager::USER_TYPE_SUPERVISED) {
-      UserContext updated_context = UserManager::Get()
+      UserContext updated_context = ChromeUserManager::Get()
                                         ->GetSupervisedUserManager()
                                         ->GetAuthentication()
                                         ->TransformKey(user_context);
@@ -348,7 +350,7 @@ void ScreenLocker::HandleLockScreenRequest() {
     return;
   }
   if (g_screen_lock_observer->session_started() &&
-      UserManager::Get()->CanCurrentUserLock()) {
+      user_manager::UserManager::Get()->CanCurrentUserLock()) {
     ScreenLocker::Show();
     ash::Shell::GetInstance()->lock_state_controller()->OnStartingLock();
   } else {
@@ -370,8 +372,8 @@ void ScreenLocker::Show() {
   // Check whether the currently logged in user is a guest account and if so,
   // refuse to lock the screen (crosbug.com/23764).
   // For a demo user, we should never show the lock screen (crosbug.com/27647).
-  if (UserManager::Get()->IsLoggedInAsGuest() ||
-      UserManager::Get()->IsLoggedInAsDemoUser()) {
+  if (user_manager::UserManager::Get()->IsLoggedInAsGuest() ||
+      user_manager::UserManager::Get()->IsLoggedInAsDemoUser()) {
     VLOG(1) << "Refusing to lock screen for guest/demo account";
     return;
   }
@@ -390,7 +392,7 @@ void ScreenLocker::Show() {
 
   if (!screen_locker_) {
     ScreenLocker* locker =
-        new ScreenLocker(UserManager::Get()->GetUnlockUsers());
+        new ScreenLocker(user_manager::UserManager::Get()->GetUnlockUsers());
     VLOG(1) << "Created ScreenLocker " << locker;
     locker->Init();
   } else {
@@ -405,8 +407,8 @@ void ScreenLocker::Show() {
 void ScreenLocker::Hide() {
   DCHECK(base::MessageLoopForUI::IsCurrent());
   // For a guest/demo user, screen_locker_ would have never been initialized.
-  if (UserManager::Get()->IsLoggedInAsGuest() ||
-      UserManager::Get()->IsLoggedInAsDemoUser()) {
+  if (user_manager::UserManager::Get()->IsLoggedInAsGuest() ||
+      user_manager::UserManager::Get()->IsLoggedInAsDemoUser()) {
     VLOG(1) << "Refusing to hide lock screen for guest/demo account";
     return;
   }
diff --git a/chrome/browser/chromeos/login/lock/webui_screen_locker.cc b/chrome/browser/chromeos/login/lock/webui_screen_locker.cc
index 628bb72..d0876ee 100644
--- a/chrome/browser/chromeos/login/lock/webui_screen_locker.cc
+++ b/chrome/browser/chromeos/login/lock/webui_screen_locker.cc
@@ -17,7 +17,6 @@
 #include "chrome/browser/chromeos/login/helper.h"
 #include "chrome/browser/chromeos/login/lock/screen_locker.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_display.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/ui/webui/chromeos/login/oobe_ui.h"
 #include "chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h"
 #include "chrome/common/url_constants.h"
diff --git a/chrome/browser/chromeos/login/login_manager_test.cc b/chrome/browser/chromeos/login/login_manager_test.cc
index 6d5445a..40a5836 100644
--- a/chrome/browser/chromeos/login/login_manager_test.cc
+++ b/chrome/browser/chromeos/login/login_manager_test.cc
@@ -10,11 +10,11 @@
 #include "chrome/browser/chromeos/login/existing_user_controller.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_view.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/login/auth/key.h"
 #include "chromeos/login/auth/user_context.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/test/browser_test_utils.h"
@@ -68,7 +68,7 @@ bool LoginManagerTest::TryToLogin(const UserContext& user_context) {
   if (!AddUserToSession(user_context))
     return false;
   if (const user_manager::User* active_user =
-          UserManager::Get()->GetActiveUser())
+          user_manager::UserManager::Get()->GetActiveUser())
     return active_user->email() == user_context.GetUserID();
   return false;
 }
@@ -85,7 +85,7 @@ bool LoginManagerTest::AddUserToSession(const UserContext& user_context) {
       chrome::NOTIFICATION_SESSION_STARTED,
       content::NotificationService::AllSources()).Wait();
   const user_manager::UserList& logged_users =
-      UserManager::Get()->GetLoggedInUsers();
+      user_manager::UserManager::Get()->GetLoggedInUsers();
   for (user_manager::UserList::const_iterator it = logged_users.begin();
        it != logged_users.end();
        ++it) {
diff --git a/chrome/browser/chromeos/login/login_screen_policy_browsertest.cc b/chrome/browser/chromeos/login/login_screen_policy_browsertest.cc
index 9743499..d5a4f1f 100644
--- a/chrome/browser/chromeos/login/login_screen_policy_browsertest.cc
+++ b/chrome/browser/chromeos/login/login_screen_policy_browsertest.cc
@@ -4,12 +4,12 @@
 
 #include "base/command_line.h"
 #include "base/memory/ref_counted.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/device_policy_cros_browser_test.h"
 #include "chrome/browser/chromeos/policy/proto/chrome_device_policy.pb.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/settings/cros_settings_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/test/test_utils.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -31,7 +31,7 @@ class LoginScreenPolicyTest : public policy::DevicePolicyCrosBrowserTest {
 };
 
 IN_PROC_BROWSER_TEST_F(LoginScreenPolicyTest, DisableSupervisedUsers) {
-  EXPECT_FALSE(chromeos::UserManager::Get()->AreSupervisedUsersAllowed());
+  EXPECT_FALSE(user_manager::UserManager::Get()->AreSupervisedUsersAllowed());
 
   scoped_refptr<content::MessageLoopRunner> runner(
       new content::MessageLoopRunner);
@@ -46,7 +46,7 @@ IN_PROC_BROWSER_TEST_F(LoginScreenPolicyTest, DisableSupervisedUsers) {
 
   runner->Run();
 
-  EXPECT_TRUE(chromeos::UserManager::Get()->AreSupervisedUsersAllowed());
+  EXPECT_TRUE(user_manager::UserManager::Get()->AreSupervisedUsersAllowed());
 }
 
 }  // namespace chromeos
diff --git a/chrome/browser/chromeos/login/login_utils.cc b/chrome/browser/chromeos/login/login_utils.cc
index 5ed36b9..37566ae 100644
--- a/chrome/browser/chromeos/login/login_utils.cc
+++ b/chrome/browser/chromeos/login/login_utils.cc
@@ -50,8 +50,9 @@
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/ui/input_events_blocker.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host.h"
+#include "chrome/browser/chromeos/login/user_flow.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ -80,6 +81,7 @@
 #include "chromeos/settings/cros_settings_names.h"
 #include "components/signin/core/browser/signin_manager.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "google_apis/gaia/gaia_auth_consumer.h"
@@ -106,11 +108,11 @@ CommandLine CreatePerSessionCommandLine(Profile* profile) {
 // Returns true if restart is needed to apply per-session flags.
 bool NeedRestartToApplyPerSessionFlags(const CommandLine& user_flags) {
   // Don't restart browser if it is not first profile in session.
-  if (UserManager::Get()->GetLoggedInUsers().size() != 1)
+  if (user_manager::UserManager::Get()->GetLoggedInUsers().size() != 1)
     return false;
 
   // Only restart if needed and if not going into managed mode.
-  if (UserManager::Get()->IsLoggedInAsSupervisedUser())
+  if (user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser())
     return false;
 
   if (about_flags::AreSwitchesIdenticalToCurrentCommandLine(
@@ -247,8 +249,8 @@ void LoginUtilsImpl::DoBrowserLaunchInternal(Profile* profile,
     return;
   }
 
-  if (!UserManager::Get()->GetCurrentUserFlow()->ShouldLaunchBrowser()) {
-    UserManager::Get()->GetCurrentUserFlow()->LaunchExtraSteps(profile);
+  if (!ChromeUserManager::Get()->GetCurrentUserFlow()->ShouldLaunchBrowser()) {
+    ChromeUserManager::Get()->GetCurrentUserFlow()->LaunchExtraSteps(profile);
     return;
   }
 
@@ -284,9 +286,9 @@ void LoginUtilsImpl::DoBrowserLaunchInternal(Profile* profile,
   // browser before it is dereferenced by the login host.
   if (login_host)
     login_host->Finalize();
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
   chromeos::BootTimesLoader::Get()->LoginDone(
-      chromeos::UserManager::Get()->IsCurrentUserNew());
+      user_manager::UserManager::Get()->IsCurrentUserNew());
 }
 
 // static
@@ -365,7 +367,7 @@ bool LoginUtilsImpl::RestartToApplyPerSessionFlagsIfNeed(Profile* profile,
   flags.assign(user_flags.argv().begin() + 1, user_flags.argv().end());
   VLOG(1) << "Restarting to apply per-session flags...";
   DBusThreadManager::Get()->GetSessionManagerClient()->SetFlagsForUser(
-      UserManager::Get()->GetActiveUser()->email(), flags);
+      user_manager::UserManager::Get()->GetActiveUser()->email(), flags);
   AttemptRestart(profile);
   return true;
 }
diff --git a/chrome/browser/chromeos/login/saml/saml_browsertest.cc b/chrome/browser/chromeos/login/saml/saml_browsertest.cc
index be4baca..9d2de95b 100644
--- a/chrome/browser/chromeos/login/saml/saml_browsertest.cc
+++ b/chrome/browser/chromeos/login/saml/saml_browsertest.cc
@@ -24,7 +24,6 @@
 #include "chrome/browser/chromeos/login/test/oobe_screen_waiter.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_display.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/policy/device_policy_builder.h"
 #include "chrome/browser/chromeos/policy/device_policy_cros_browser_test.h"
@@ -49,6 +48,7 @@
 #include "components/policy/core/common/policy_map.h"
 #include "components/policy/core/common/policy_types.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/test/browser_test_utils.h"
@@ -580,7 +580,8 @@ IN_PROC_BROWSER_TEST_F(SamlTest, UseAutenticatedUserEmailAddress) {
   content::WindowedNotificationObserver(
       chrome::NOTIFICATION_SESSION_STARTED,
       content::NotificationService::AllSources()).Wait();
-  const user_manager::User* user = UserManager::Get()->GetActiveUser();
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->GetActiveUser();
   ASSERT_TRUE(user);
   EXPECT_EQ(kFirstSAMLUserEmail, user->email());
 }
@@ -737,11 +738,11 @@ void SAMLPolicyTest::SetUpOnMainThread() {
   SamlTest::SetUpOnMainThread();
 
   // Pretend that the test users' OAuth tokens are valid.
-  UserManager::Get()->SaveUserOAuthStatus(
+  user_manager::UserManager::Get()->SaveUserOAuthStatus(
       kFirstSAMLUserEmail, user_manager::User::OAUTH2_TOKEN_STATUS_VALID);
-  UserManager::Get()->SaveUserOAuthStatus(
+  user_manager::UserManager::Get()->SaveUserOAuthStatus(
       kNonSAMLUserEmail, user_manager::User::OAUTH2_TOKEN_STATUS_VALID);
-  UserManager::Get()->SaveUserOAuthStatus(
+  user_manager::UserManager::Get()->SaveUserOAuthStatus(
       kDifferentDomainSAMLUserEmail,
       user_manager::User::OAUTH2_TOKEN_STATUS_VALID);
 }
@@ -818,7 +819,7 @@ std::string SAMLPolicyTest::GetCookieValue(const std::string& name) {
 
 void SAMLPolicyTest::GetCookies() {
   Profile* profile = chromeos::ProfileHelper::Get()->GetProfileByUserUnsafe(
-      UserManager::Get()->GetActiveUser());
+      user_manager::UserManager::Get()->GetActiveUser());
   ASSERT_TRUE(profile);
   base::RunLoop run_loop;
   content::BrowserThread::PostTask(
diff --git a/chrome/browser/chromeos/login/saml/saml_offline_signin_limiter.cc b/chrome/browser/chromeos/login/saml/saml_offline_signin_limiter.cc
index 8922981..42321e3 100644
--- a/chrome/browser/chromeos/login/saml/saml_offline_signin_limiter.cc
+++ b/chrome/browser/chromeos/login/saml/saml_offline_signin_limiter.cc
@@ -13,12 +13,12 @@
 #include "base/prefs/pref_service.h"
 #include "base/time/clock.h"
 #include "base/time/time.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/pref_names.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 
 namespace chromeos {
 
@@ -56,7 +56,7 @@ void SAMLOfflineSigninLimiter::SignedIn(UserContext::AuthFlow auth_flow) {
     // a SAML IdP. No limit applies in this case. Clear the time of last login
     // with SAML and the flag enforcing online login, then return.
     prefs->ClearPref(prefs::kSAMLLastGAIASignInTime);
-    UserManager::Get()->SaveForceOnlineSignin(user_id, false);
+    user_manager::UserManager::Get()->SaveForceOnlineSignin(user_id, false);
     return;
   }
 
@@ -66,7 +66,7 @@ void SAMLOfflineSigninLimiter::SignedIn(UserContext::AuthFlow auth_flow) {
     // enforcing online login. The flag will be set again when the limit
     // expires. If the limit already expired (e.g. because it was set to zero),
     // the flag will be set again immediately.
-    UserManager::Get()->SaveForceOnlineSignin(user_id, false);
+    user_manager::UserManager::Get()->SaveForceOnlineSignin(user_id, false);
     prefs->SetInt64(prefs::kSAMLLastGAIASignInTime,
                     clock_->Now().ToInternalValue());
   }
@@ -147,7 +147,7 @@ void SAMLOfflineSigninLimiter::ForceOnlineLogin() {
     return;
   }
 
-  UserManager::Get()->SaveForceOnlineSignin(user->email(), true);
+  user_manager::UserManager::Get()->SaveForceOnlineSignin(user->email(), true);
   offline_signin_limit_timer_.reset();
 }
 
diff --git a/chrome/browser/chromeos/login/saml/saml_offline_signin_limiter_unittest.cc b/chrome/browser/chromeos/login/saml/saml_offline_signin_limiter_unittest.cc
index eefb3d9..0828fdc 100644
--- a/chrome/browser/chromeos/login/saml/saml_offline_signin_limiter_unittest.cc
+++ b/chrome/browser/chromeos/login/saml/saml_offline_signin_limiter_unittest.cc
@@ -12,7 +12,7 @@
 #include "base/time/clock.h"
 #include "chrome/browser/chromeos/login/saml/saml_offline_signin_limiter_factory.h"
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_profile.h"
diff --git a/chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc b/chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc
index 00332b4..4eecbd9 100644
--- a/chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc
+++ b/chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc
@@ -13,7 +13,6 @@
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_process_platform_part.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/ui/webui/chromeos/login/l10n_util.h"
 #include "chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h"
@@ -22,6 +21,7 @@
 #include "components/policy/core/common/policy_map.h"
 #include "components/policy/core/common/policy_types.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "policy/policy_constants.h"
 
@@ -152,7 +152,8 @@ void ChromeUserSelectionScreen::CheckForPublicSessionLocalePolicyChange(
 
 void ChromeUserSelectionScreen::SetPublicSessionDisplayName(
     const std::string& user_id) {
-  const user_manager::User* user = UserManager::Get()->FindUser(user_id);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(user_id);
   if (!user || user->GetType() != user_manager::USER_TYPE_PUBLIC_ACCOUNT)
     return;
 
diff --git a/chrome/browser/chromeos/login/screens/user_image_screen.cc b/chrome/browser/chromeos/login/screens/user_image_screen.cc
index b1f3391..bd709db 100644
--- a/chrome/browser/chromeos/login/screens/user_image_screen.cc
+++ b/chrome/browser/chromeos/login/screens/user_image_screen.cc
@@ -21,7 +21,7 @@
 #include "chrome/browser/chromeos/login/login_utils.h"
 #include "chrome/browser/chromeos/login/screens/screen_observer.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/policy/profile_policy_connector.h"
@@ -34,6 +34,7 @@
 #include "components/user_manager/user.h"
 #include "components/user_manager/user_image/default_user_images.h"
 #include "components/user_manager/user_image/user_image.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "policy/policy_constants.h"
@@ -219,11 +220,11 @@ void UserImageScreen::PrepareToShow() {
 }
 
 const user_manager::User* UserImageScreen::GetUser() {
-  return UserManager::Get()->GetLoggedInUser();
+  return user_manager::UserManager::Get()->GetLoggedInUser();
 }
 
 UserImageManager* UserImageScreen::GetUserImageManager() {
-  return UserManager::Get()->GetUserImageManager(GetUser()->email());
+  return ChromeUserManager::Get()->GetUserImageManager(GetUser()->email());
 }
 
 UserImageSyncObserver* UserImageScreen::GetSyncObserver() {
diff --git a/chrome/browser/chromeos/login/screens/user_image_screen.h b/chrome/browser/chromeos/login/screens/user_image_screen.h
index 506901e..5783e29 100644
--- a/chrome/browser/chromeos/login/screens/user_image_screen.h
+++ b/chrome/browser/chromeos/login/screens/user_image_screen.h
@@ -27,6 +27,8 @@ class PolicyChangeRegistrar;
 
 namespace chromeos {
 
+class UserImageManager;
+
 class UserImageScreen: public WizardScreen,
                        public UserImageScreenActor::Delegate,
                        public ImageDecoder::Delegate,
diff --git a/chrome/browser/chromeos/login/screens/user_selection_screen.cc b/chrome/browser/chromeos/login/screens/user_selection_screen.cc
index 78a296e..41c3024 100644
--- a/chrome/browser/chromeos/login/screens/user_selection_screen.cc
+++ b/chrome/browser/chromeos/login/screens/user_selection_screen.cc
@@ -14,13 +14,14 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_process_platform_part.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/multi_profile_user_controller.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/signin/screenlock_bridge.h"
 #include "chrome/browser/ui/webui/chromeos/login/l10n_util.h"
 #include "chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h"
 #include "chrome/common/pref_names.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "ui/wm/core/user_activity_detector.h"
 
@@ -136,7 +137,7 @@ void UserSelectionScreen::FillUserDictionary(
   // Fill in multi-profiles related fields.
   if (is_signin_to_add) {
     MultiProfileUserController* multi_profile_user_controller =
-        UserManager::Get()->GetMultiProfileUserController();
+        ChromeUserManager::Get()->GetMultiProfileUserController();
     MultiProfileUserController::UserAllowedInSessionReason isUserAllowedReason;
     bool isUserAllowed = multi_profile_user_controller->IsUserAllowedInSession(
         user_id, &isUserAllowedReason);
@@ -299,7 +300,7 @@ void UserSelectionScreen::SendUserList() {
   // http://crbug.com/230852
   bool single_user = users.size() == 1;
   bool is_signin_to_add = LoginDisplayHostImpl::default_host() &&
-                          UserManager::Get()->IsUserLoggedIn();
+                          user_manager::UserManager::Get()->IsUserLoggedIn();
   std::string owner;
   chromeos::CrosSettings::Get()->GetString(chromeos::kDeviceOwner, &owner);
 
diff --git a/chrome/browser/chromeos/login/session/chrome_session_manager.cc b/chrome/browser/chromeos/login/session/chrome_session_manager.cc
index 73f1720..d4077b6 100644
--- a/chrome/browser/chromeos/login/session/chrome_session_manager.cc
+++ b/chrome/browser/chromeos/login/session/chrome_session_manager.cc
@@ -14,7 +14,6 @@
 #include "chrome/browser/chromeos/login/session/login_oobe_session_manager_delegate.h"
 #include "chrome/browser/chromeos/login/session/restore_after_crash_session_manager_delegate.h"
 #include "chrome/browser/chromeos/login/session/stub_login_session_manager_delegate.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/login/user_names.h"
diff --git a/chrome/browser/chromeos/login/session/restore_after_crash_session_manager_delegate.cc b/chrome/browser/chromeos/login/session/restore_after_crash_session_manager_delegate.cc
index 31c6513..1b43698 100644
--- a/chrome/browser/chromeos/login/session/restore_after_crash_session_manager_delegate.cc
+++ b/chrome/browser/chromeos/login/session/restore_after_crash_session_manager_delegate.cc
@@ -7,11 +7,11 @@
 #include "base/command_line.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/session/user_session_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/chrome_switches.h"
 #include "chromeos/audio/cras_audio_handler.h"
 #include "chromeos/chromeos_switches.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 
 namespace chromeos {
@@ -48,7 +48,7 @@ void RestoreAfterCrashSessionManagerDelegate::Start() {
         content::Details<Profile>(profile()));
 
     // This call will set session state to SESSION_STATE_ACTIVE (same one).
-    UserManager::Get()->SessionStarted();
+    user_manager::UserManager::Get()->SessionStarted();
 
     // Now is the good time to retrieve other logged in users for this session.
     // First user has been already marked as logged in and active in
diff --git a/chrome/browser/chromeos/login/session/user_session_manager.cc b/chrome/browser/chromeos/login/session/user_session_manager.cc
index d9eb16d..1a654b5 100644
--- a/chrome/browser/chromeos/login/session/user_session_manager.cc
+++ b/chrome/browser/chromeos/login/session/user_session_manager.cc
@@ -31,8 +31,8 @@
 #include "chrome/browser/chromeos/login/saml/saml_offline_signin_limiter_factory.h"
 #include "chrome/browser/chromeos/login/signin/oauth2_login_manager.h"
 #include "chrome/browser/chromeos/login/signin/oauth2_login_manager_factory.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service_factory.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
@@ -64,6 +64,7 @@
 #include "components/session_manager/core/session_manager.h"
 #include "components/signin/core/browser/signin_manager_base.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
@@ -190,7 +191,7 @@ void UserSessionManager::OverrideHomedir() {
   // Override user homedir, check for ProfileManager being initialized as
   // it may not exist in unit tests.
   if (g_browser_process->profile_manager()) {
-    UserManager* user_manager = UserManager::Get();
+    user_manager::UserManager* user_manager = user_manager::UserManager::Get();
     if (user_manager->GetLoggedInUsers().size() == 1) {
       base::FilePath homedir = ProfileHelper::GetProfilePathByUserIdHash(
           user_manager->GetPrimaryUser()->username_hash());
@@ -248,7 +249,7 @@ void UserSessionManager::StartSession(
 }
 
 void UserSessionManager::PerformPostUserLoggedInActions() {
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (user_manager->GetLoggedInUsers().size() == 1) {
     // Owner must be first user in session. DeviceSettingsService can't deal
     // with multiple user and will mix up ownership, crbug.com/230018.
@@ -263,7 +264,7 @@ void UserSessionManager::PerformPostUserLoggedInActions() {
 }
 
 void UserSessionManager::RestoreAuthenticationSession(Profile* user_profile) {
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   // We need to restore session only for logged in regular (GAIA) users.
   // Note: stub user is a special case that is used for tests, running
   // linux_chromeos build on dev workstations w/o user_id parameters.
@@ -366,7 +367,7 @@ bool UserSessionManager::RespectLocalePreference(
   if (g_browser_process == NULL)
     return false;
 
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (!user || (user_manager->IsUserLoggedIn() &&
                 user != user_manager->GetPrimaryUser())) {
     return false;
@@ -426,7 +427,8 @@ bool UserSessionManager::RespectLocalePreference(
   //
   // For Guest mode, user locale preferences will never get initialized.
   // So input methods should be enabled somewhere.
-  const bool enable_layouts = UserManager::Get()->IsLoggedInAsGuest();
+  const bool enable_layouts =
+      user_manager::UserManager::Get()->IsLoggedInAsGuest();
   locale_util::SwitchLanguage(pref_locale,
                               enable_layouts,
                               false /* login_layouts_only */,
@@ -476,8 +478,8 @@ void UserSessionManager::OnSessionRestoreStateChanged(
   // error. http://crbug.com/295245
   if (!connection_error) {
     // We are in one of "done" states here.
-    UserManager::Get()->SaveUserOAuthStatus(
-        UserManager::Get()->GetLoggedInUser()->email(),
+    user_manager::UserManager::Get()->SaveUserOAuthStatus(
+        user_manager::UserManager::Get()->GetLoggedInUser()->email(),
         user_status);
   }
 
@@ -494,8 +496,8 @@ void UserSessionManager::OnNewRefreshTokenAvaiable(Profile* user_profile) {
   login_manager->RemoveObserver(this);
 
   // Mark user auth token status as valid.
-  UserManager::Get()->SaveUserOAuthStatus(
-      UserManager::Get()->GetLoggedInUser()->email(),
+  user_manager::UserManager::Get()->SaveUserOAuthStatus(
+      user_manager::UserManager::Get()->GetLoggedInUser()->email(),
       user_manager::User::OAUTH2_TOKEN_STATUS_VALID);
 
   VLOG(1) << "Exiting after new refresh token fetched";
@@ -511,7 +513,7 @@ void UserSessionManager::OnConnectionTypeChanged(
       base::CommandLine::ForCurrentProcess()->HasSwitch(
           ::switches::kTestName) ||
       base::CommandLine::ForCurrentProcess()->HasSwitch(::switches::kTestType);
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (type == net::NetworkChangeNotifier::CONNECTION_NONE ||
       !user_manager->IsUserLoggedIn() ||
       !user_manager->IsLoggedInAsRegularUser() ||
@@ -585,7 +587,7 @@ void UserSessionManager::StartCrosSession() {
 void UserSessionManager::NotifyUserLoggedIn() {
   BootTimesLoader* btl = BootTimesLoader::Get();
   btl->AddLoginTimeMarker("UserLoggedIn-Start", false);
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   user_manager->UserLoggedIn(user_context_.GetUserID(),
                              user_context_.GetUserIDHash(),
                              false);
@@ -640,20 +642,21 @@ void UserSessionManager::OnProfileCreated(const UserContext& user_context,
 void UserSessionManager::InitProfilePreferences(
     Profile* profile,
     const UserContext& user_context) {
-  if (UserManager::Get()->IsCurrentUserNew()) {
+  if (user_manager::UserManager::Get()->IsCurrentUserNew()) {
     SetFirstLoginPrefs(profile->GetPrefs(),
                        user_context.GetPublicSessionLocale(),
                        user_context.GetPublicSessionInputMethod());
   }
 
-  if (UserManager::Get()->IsLoggedInAsSupervisedUser()) {
-    user_manager::User* active_user = UserManager::Get()->GetActiveUser();
+  if (user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser()) {
+    user_manager::User* active_user =
+        user_manager::UserManager::Get()->GetActiveUser();
     std::string supervised_user_sync_id =
-        UserManager::Get()->GetSupervisedUserManager()->
-            GetUserSyncId(active_user->email());
+        ChromeUserManager::Get()->GetSupervisedUserManager()->GetUserSyncId(
+            active_user->email());
     profile->GetPrefs()->SetString(prefs::kSupervisedUserId,
                                    supervised_user_sync_id);
-  } else if (UserManager::Get()->IsLoggedInAsRegularUser()) {
+  } else if (user_manager::UserManager::Get()->IsLoggedInAsRegularUser()) {
     // Make sure that the google service username is properly set (we do this
     // on every sign in, not just the first login, to deal with existing
     // profiles that might not have it set yet).
@@ -743,7 +746,7 @@ void UserSessionManager::FinalizePrepareProfile(Profile* profile) {
   }
   btl->AddLoginTimeMarker("TPMOwn-End", false);
 
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (user_manager->IsLoggedInAsRegularUser()) {
     SAMLOfflineSigninLimiter* saml_offline_signin_limiter =
         SAMLOfflineSigninLimiterFactory::GetForProfile(profile);
@@ -867,8 +870,10 @@ void UserSessionManager::InitRlzImpl(Profile* profile, bool disabled) {
   // Negative ping delay means to send ping immediately after a first search is
   // recorded.
   RLZTracker::InitRlzFromProfileDelayed(
-      profile, UserManager::Get()->IsCurrentUserNew(),
-      ping_delay < 0, base::TimeDelta::FromMilliseconds(abs(ping_delay)));
+      profile,
+      user_manager::UserManager::Get()->IsCurrentUserNew(),
+      ping_delay < 0,
+      base::TimeDelta::FromMilliseconds(abs(ping_delay)));
   if (delegate_)
     delegate_->OnRlzInitialized();
 #endif
@@ -909,7 +914,7 @@ void UserSessionManager::OnRestoreActiveSessions(
   }
 
   // One profile has been already loaded on browser start.
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   DCHECK(user_manager->GetLoggedInUsers().size() == 1);
   DCHECK(user_manager->GetActiveUser());
   std::string active_user_id = user_manager->GetActiveUser()->email();
@@ -940,7 +945,7 @@ void UserSessionManager::RestorePendingUserSessions() {
 
   // Check that this user is not logged in yet.
   user_manager::UserList logged_in_users =
-      UserManager::Get()->GetLoggedInUsers();
+      user_manager::UserManager::Get()->GetLoggedInUsers();
   bool user_already_logged_in = false;
   for (user_manager::UserList::const_iterator it = logged_in_users.begin();
        it != logged_in_users.end();
diff --git a/chrome/browser/chromeos/login/signin/auth_sync_observer.cc b/chrome/browser/chromeos/login/signin/auth_sync_observer.cc
index f780776..6878da0 100644
--- a/chrome/browser/chromeos/login/signin/auth_sync_observer.cc
+++ b/chrome/browser/chromeos/login/signin/auth_sync_observer.cc
@@ -7,12 +7,13 @@
 #include "base/metrics/user_metrics.h"
 #include "base/metrics/user_metrics_action.h"
 #include "base/prefs/pref_service.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "chrome/browser/sync/profile_sync_service_factory.h"
 #include "chrome/common/pref_names.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/user_metrics.h"
 #include "google_apis/gaia/gaia_auth_util.h"
@@ -44,8 +45,8 @@ void AuthSyncObserver::Shutdown() {
 }
 
 void AuthSyncObserver::OnStateChanged() {
-  DCHECK(UserManager::Get()->IsLoggedInAsRegularUser() ||
-         UserManager::Get()->IsLoggedInAsSupervisedUser());
+  DCHECK(user_manager::UserManager::Get()->IsLoggedInAsRegularUser() ||
+         user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser());
   ProfileSyncService* sync_service =
       ProfileSyncServiceFactory::GetForProfile(profile_);
   user_manager::User* user = ProfileHelper::Get()->GetUserByProfile(profile_);
@@ -65,15 +66,17 @@ void AuthSyncObserver::OnStateChanged() {
     // TODO(nkostyelv): Change observer after active user has changed.
     user_manager::User::OAuthTokenStatus old_status =
         user->oauth_token_status();
-    UserManager::Get()->SaveUserOAuthStatus(
+    user_manager::UserManager::Get()->SaveUserOAuthStatus(
         email, user_manager::User::OAUTH2_TOKEN_STATUS_INVALID);
     if (user->GetType() == user_manager::USER_TYPE_SUPERVISED &&
         old_status != user_manager::User::OAUTH2_TOKEN_STATUS_INVALID) {
        // Attempt to restore token from file.
-       UserManager::Get()->GetSupervisedUserManager()->LoadSupervisedUserToken(
-           profile_,
-           base::Bind(&AuthSyncObserver::OnSupervisedTokenLoaded,
-               base::Unretained(this)));
+      ChromeUserManager::Get()
+          ->GetSupervisedUserManager()
+          ->LoadSupervisedUserToken(
+              profile_,
+              base::Bind(&AuthSyncObserver::OnSupervisedTokenLoaded,
+                         base::Unretained(this)));
        content::RecordAction(
            base::UserMetricsAction("ManagedUsers_Chromeos_Sync_Invalidated"));
     }
@@ -83,7 +86,7 @@ void AuthSyncObserver::OnStateChanged() {
             user_manager::User::OAUTH2_TOKEN_STATUS_INVALID) {
       LOG(ERROR) <<
           "Got an incorrectly invalidated token case, restoring token status.";
-      UserManager::Get()->SaveUserOAuthStatus(
+      user_manager::UserManager::Get()->SaveUserOAuthStatus(
           user->email(), user_manager::User::OAUTH2_TOKEN_STATUS_VALID);
        content::RecordAction(
            base::UserMetricsAction("ManagedUsers_Chromeos_Sync_Recovered"));
@@ -92,7 +95,7 @@ void AuthSyncObserver::OnStateChanged() {
 }
 
 void AuthSyncObserver::OnSupervisedTokenLoaded(const std::string& token) {
-  UserManager::Get()->GetSupervisedUserManager()->ConfigureSyncWithToken(
+  ChromeUserManager::Get()->GetSupervisedUserManager()->ConfigureSyncWithToken(
       profile_, token);
 }
 
diff --git a/chrome/browser/chromeos/login/signin/merge_session_load_page_unittest.cc b/chrome/browser/chromeos/login/signin/merge_session_load_page_unittest.cc
index 02afa07..b23327b 100644
--- a/chrome/browser/chromeos/login/signin/merge_session_load_page_unittest.cc
+++ b/chrome/browser/chromeos/login/signin/merge_session_load_page_unittest.cc
@@ -7,7 +7,7 @@
 #include "chrome/browser/chromeos/login/signin/merge_session_load_page.h"
 #include "chrome/browser/chromeos/login/signin/oauth2_login_manager.h"
 #include "chrome/browser/chromeos/login/signin/oauth2_login_manager_factory.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #include "chrome/test/base/chrome_render_view_host_test_harness.h"
diff --git a/chrome/browser/chromeos/login/signin/merge_session_throttle.cc b/chrome/browser/chromeos/login/signin/merge_session_throttle.cc
index ce9b7a7..b8f8b02 100644
--- a/chrome/browser/chromeos/login/signin/merge_session_throttle.cc
+++ b/chrome/browser/chromeos/login/signin/merge_session_throttle.cc
@@ -16,10 +16,9 @@
 #include "chrome/browser/chromeos/login/signin/merge_session_xhr_request_waiter.h"
 #include "chrome/browser/chromeos/login/signin/oauth2_login_manager.h"
 #include "chrome/browser/chromeos/login/signin/oauth2_login_manager_factory.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/common/url_constants.h"
 #include "components/google/core/browser/google_util.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/resource_controller.h"
@@ -163,9 +162,9 @@ bool MergeSessionThrottle::ShouldDelayRequest(
     int render_view_id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-  if (!chromeos::UserManager::Get()->IsUserLoggedIn()) {
+  if (!user_manager::UserManager::Get()->IsUserLoggedIn()) {
     return false;
-  } else if (!chromeos::UserManager::Get()->IsLoggedInAsRegularUser()) {
+  } else if (!user_manager::UserManager::Get()->IsLoggedInAsRegularUser()) {
     // This is not a regular user session, let's remove the throttle
     // permanently.
     if (!AreAllSessionMergedAlready())
@@ -206,8 +205,8 @@ bool MergeSessionThrottle::ShouldDelayRequest(
       // In theory this should not happen since we should
       // kick off the session restore process for the newly added profile
       // before we attempt loading any page.
-      if (chromeos::UserManager::Get()->IsLoggedInAsRegularUser() &&
-          !chromeos::UserManager::Get()->IsLoggedInAsStub()) {
+      if (user_manager::UserManager::Get()->IsLoggedInAsRegularUser() &&
+          !user_manager::UserManager::Get()->IsLoggedInAsStub()) {
         LOG(WARNING) << "Loading content for a profile without "
                      << "session restore?";
       }
diff --git a/chrome/browser/chromeos/login/signin/oauth2_browsertest.cc b/chrome/browser/chromeos/login/signin/oauth2_browsertest.cc
index 00677ec..edf53d9 100644
--- a/chrome/browser/chromeos/login/signin/oauth2_browsertest.cc
+++ b/chrome/browser/chromeos/login/signin/oauth2_browsertest.cc
@@ -14,7 +14,6 @@
 #include "chrome/browser/chromeos/login/signin/oauth2_login_manager_factory.h"
 #include "chrome/browser/chromeos/login/signin_specifics.h"
 #include "chrome/browser/chromeos/login/test/oobe_base_test.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/extensions/extension_test_message_listener.h"
 #include "chrome/browser/profiles/profile_manager.h"
@@ -31,6 +30,7 @@
 #include "chromeos/login/auth/user_context.h"
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/test/browser_test_utils.h"
 #include "extensions/browser/process_manager.h"
@@ -192,8 +192,9 @@ class OAuth2Test : public OobeBaseTest {
       return false;
 
     if (const user_manager::User* active_user =
-            UserManager::Get()->GetActiveUser())
+            user_manager::UserManager::Get()->GetActiveUser()) {
       return active_user->email() == username;
+    }
 
     return false;
   }
@@ -217,7 +218,7 @@ class OAuth2Test : public OobeBaseTest {
  protected:
   // OobeBaseTest overrides.
   virtual Profile* profile() OVERRIDE {
-    if (UserManager::Get()->GetActiveUser())
+    if (user_manager::UserManager::Get()->GetActiveUser())
       return ProfileManager::GetPrimaryUserProfile();
 
     return OobeBaseTest::profile();
@@ -239,7 +240,7 @@ class OAuth2Test : public OobeBaseTest {
         chrome::NOTIFICATION_SESSION_STARTED,
         content::NotificationService::AllSources()).Wait();
     const user_manager::UserList& logged_users =
-        UserManager::Get()->GetLoggedInUsers();
+        user_manager::UserManager::Get()->GetLoggedInUsers();
     for (user_manager::UserList::const_iterator it = logged_users.begin();
          it != logged_users.end();
          ++it) {
diff --git a/chrome/browser/chromeos/login/signin/oauth2_login_manager.cc b/chrome/browser/chromeos/login/signin/oauth2_login_manager.cc
index 9bdf0b4..122d679 100644
--- a/chrome/browser/chromeos/login/signin/oauth2_login_manager.cc
+++ b/chrome/browser/chromeos/login/signin/oauth2_login_manager.cc
@@ -12,7 +12,6 @@
 #include "base/prefs/pref_service.h"
 #include "base/strings/string_util.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/signin/chrome_signin_client_factory.h"
 #include "chrome/browser/signin/profile_oauth2_token_service_factory.h"
@@ -22,6 +21,7 @@
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
 #include "components/signin/core/browser/signin_client.h"
 #include "components/signin/core/browser/signin_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 #include "google_apis/gaia/gaia_constants.h"
 #include "google_apis/gaia/gaia_urls.h"
@@ -111,7 +111,7 @@ void OAuth2LoginManager::RestoreSessionFromSavedTokens() {
     // and OnRefreshTokenAvailable is not called. Flagging it here would
     // cause user to go through Gaia in next login to obtain a new refresh
     // token.
-    UserManager::Get()->SaveUserOAuthStatus(
+    user_manager::UserManager::Get()->SaveUserOAuthStatus(
         primary_account_id, user_manager::User::OAUTH_TOKEN_STATUS_UNKNOWN);
 
     token_service->LoadCredentials(primary_account_id);
@@ -140,14 +140,14 @@ void OAuth2LoginManager::OnRefreshTokenAvailable(
 
   // Do not validate tokens for supervised users, as they don't actually have
   // oauth2 token.
-  if (UserManager::Get()->IsLoggedInAsSupervisedUser()) {
+  if (user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser()) {
     VLOG(1) << "Logged in as supervised user, skip token validation.";
     return;
   }
   // Only restore session cookies for the primary account in the profile.
   if (GetPrimaryAccountId() == account_id) {
     // Token is loaded. Undo the flagging before token loading.
-    UserManager::Get()->SaveUserOAuthStatus(
+    user_manager::UserManager::Get()->SaveUserOAuthStatus(
         account_id, user_manager::User::OAUTH2_TOKEN_STATUS_VALID);
     VerifySessionCookies();
   }
diff --git a/chrome/browser/chromeos/login/supervised/supervised_user_authentication.cc b/chrome/browser/chromeos/login/supervised/supervised_user_authentication.cc
index a7889eb..bd65b30 100644
--- a/chrome/browser/chromeos/login/supervised/supervised_user_authentication.cc
+++ b/chrome/browser/chromeos/login/supervised/supervised_user_authentication.cc
@@ -13,11 +13,11 @@
 #include "base/threading/sequenced_worker_pool.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_constants.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chromeos/cryptohome/signed_secret.pb.h"
 #include "chromeos/login/auth/key.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "crypto/hmac.h"
 #include "crypto/random.h"
@@ -224,7 +224,7 @@ void SupervisedUserAuthentication::ScheduleSupervisedPasswordChange(
     const std::string& supervised_user_id,
     const base::DictionaryValue* password_data) {
   const user_manager::User* user =
-      UserManager::Get()->FindUser(supervised_user_id);
+      user_manager::UserManager::Get()->FindUser(supervised_user_id);
   base::FilePath profile_path = ProfileHelper::GetProfilePathByUserIdHash(
       user->username_hash());
   JSONFileValueSerializer serializer(profile_path.Append(kPasswordUpdateFile));
@@ -281,7 +281,8 @@ void SupervisedUserAuthentication::LoadPasswordUpdateData(
     const std::string& user_id,
     const PasswordDataCallback& success_callback,
     const base::Closure& failure_callback) {
-  const user_manager::User* user = UserManager::Get()->FindUser(user_id);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(user_id);
   base::FilePath profile_path =
       ProfileHelper::GetProfilePathByUserIdHash(user->username_hash());
   PostTaskAndReplyWithResult(
diff --git a/chrome/browser/chromeos/login/supervised/supervised_user_creation_browsertest.cc b/chrome/browser/chromeos/login/supervised/supervised_user_creation_browsertest.cc
index bda8ca2..8ac7f8d 100644
--- a/chrome/browser/chromeos/login/supervised/supervised_user_creation_browsertest.cc
+++ b/chrome/browser/chromeos/login/supervised/supervised_user_creation_browsertest.cc
@@ -159,7 +159,7 @@ IN_PROC_BROWSER_TEST_F(SupervisedUserTransactionCleanupTest,
   std::string user_id = registration_utility_stub_->supervised_user_id();
 
   // Make sure user is already in list.
-  ASSERT_EQ(3UL, UserManager::Get()->GetUsers().size());
+  ASSERT_EQ(3UL, user_manager::UserManager::Get()->GetUsers().size());
 
   // We wait for token now. Press cancel button at this point.
   JSEval("$('cancel-add-user-button').click()");
@@ -171,7 +171,7 @@ IN_PROC_BROWSER_TEST_(
     SupervisedUserTransactionCleanupTest2,
     testing::internal::GetTypeId<SupervisedUserTransactionCleanupTest>()) {
   // Make sure there is no supervised user in list.
-  ASSERT_EQ(2UL, UserManager::Get()->GetUsers().size());
+  ASSERT_EQ(2UL, user_manager::UserManager::Get()->GetUsers().size());
 }
 
 }  // namespace chromeos
diff --git a/chrome/browser/chromeos/login/supervised/supervised_user_creation_controller_new.cc b/chrome/browser/chromeos/login/supervised/supervised_user_creation_controller_new.cc
index 56211fc..45cd784 100644
--- a/chrome/browser/chromeos/login/supervised/supervised_user_creation_controller_new.cc
+++ b/chrome/browser/chromeos/login/supervised/supervised_user_creation_controller_new.cc
@@ -17,8 +17,8 @@
 #include "chrome/browser/chromeos/login/auth/mount_manager.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_authentication.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_constants.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "chrome/browser/sync/profile_sync_service_factory.h"
@@ -28,6 +28,7 @@
 #include "chromeos/login/auth/key.h"
 #include "chromeos/login/auth/user_context.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/user_metrics.h"
 #include "crypto/random.h"
@@ -148,7 +149,7 @@ void SupervisedUserCreationControllerNew::StartCreationImpl() {
   VLOG(1) << " Phase 1 : Prepare keys";
 
   SupervisedUserManager* manager =
-      UserManager::Get()->GetSupervisedUserManager();
+      ChromeUserManager::Get()->GetSupervisedUserManager();
   manager->StartCreationTransaction(creation_context_->display_name);
 
   creation_context_->local_user_id = manager->GenerateUserId();
@@ -167,7 +168,7 @@ void SupervisedUserCreationControllerNew::StartCreationImpl() {
                             creation_context_->display_name);
 
   SupervisedUserAuthentication* authentication =
-      UserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
 
   // When importing M35+ users we need only to store data, for all other cases
   // we need to create some keys.
@@ -368,14 +369,16 @@ void SupervisedUserCreationControllerNew::OnSupervisedUserFilesStored(
   }
   // Assume that new token is valid. It will be automatically invalidated if
   // sync service fails to use it.
-  UserManager::Get()->SaveUserOAuthStatus(
+  user_manager::UserManager::Get()->SaveUserOAuthStatus(
       creation_context_->local_user_id,
       user_manager::User::OAUTH2_TOKEN_STATUS_VALID);
 
   stage_ = TOKEN_WRITTEN;
 
   timeout_timer_.Stop();
-  UserManager::Get()->GetSupervisedUserManager()->CommitCreationTransaction();
+  ChromeUserManager::Get()
+      ->GetSupervisedUserManager()
+      ->CommitCreationTransaction();
   content::RecordAction(
       base::UserMetricsAction("ManagedMode_LocallyManagedUserCreated"));
 
diff --git a/chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.cc b/chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.cc
index 52ba4ab..53f5cd7 100644
--- a/chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.cc
+++ b/chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.cc
@@ -17,6 +17,7 @@
 #include "chrome/browser/chromeos/login/supervised/supervised_user_creation_controller.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_creation_controller_new.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/supervised_user/supervised_user_constants.h"
@@ -445,8 +446,8 @@ bool SupervisedUserCreationScreen::FindUserByDisplayName(
 
 void SupervisedUserCreationScreen::ApplyPicture() {
   std::string user_id = controller_->GetSupervisedUserId();
-  UserManager* user_manager = UserManager::Get();
-  UserImageManager* image_manager = user_manager->GetUserImageManager(user_id);
+  UserImageManager* image_manager =
+      ChromeUserManager::Get()->GetUserImageManager(user_id);
   switch (selected_image_) {
     case user_manager::User::USER_IMAGE_EXTERNAL:
       // Photo decoding may not have been finished yet.
@@ -485,7 +486,7 @@ void SupervisedUserCreationScreen::OnGetSupervisedUsers(
   // Copy for passing to WebUI, contains only id, name and avatar URL.
   scoped_ptr<base::ListValue> ui_users(new base::ListValue());
   SupervisedUserManager* supervised_user_manager =
-      UserManager::Get()->GetSupervisedUserManager();
+      ChromeUserManager::Get()->GetSupervisedUserManager();
 
   // Stored copy, contains all necessary information.
   existing_users_.reset(new base::DictionaryValue());
diff --git a/chrome/browser/chromeos/login/supervised/supervised_user_login_flow.cc b/chrome/browser/chromeos/login/supervised/supervised_user_login_flow.cc
index 43ce73f..d6d7fb1 100644
--- a/chrome/browser/chromeos/login/supervised/supervised_user_login_flow.cc
+++ b/chrome/browser/chromeos/login/supervised/supervised_user_login_flow.cc
@@ -15,10 +15,11 @@
 #include "chrome/browser/chromeos/login/supervised/supervised_user_constants.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chromeos/login/auth/key.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 
 using content::BrowserThread;
@@ -69,10 +70,10 @@ void SupervisedUserLoginFlow::ConfigureSync(const std::string& token) {
 
   // TODO(antrim): add error handling (no token loaded).
   // See also: http://crbug.com/312751
-  UserManager::Get()->GetSupervisedUserManager()->ConfigureSyncWithToken(
+  ChromeUserManager::Get()->GetSupervisedUserManager()->ConfigureSyncWithToken(
       profile_, token);
   SupervisedUserAuthentication* auth =
-      UserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
 
   if (auth->HasScheduledPasswordUpdate(user_id())) {
     auth->LoadPasswordUpdateData(
@@ -95,7 +96,7 @@ void SupervisedUserLoginFlow::OnPasswordChangeDataLoaded(
     const base::DictionaryValue* password_data) {
   // Edge case, when manager has signed in and already updated the password.
   SupervisedUserAuthentication* auth =
-      UserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
   if (!auth->NeedPasswordChange(user_id(), password_data)) {
     VLOG(1) << "Password already changed for " << user_id();
     auth->ClearScheduledPasswordUpdate(user_id());
@@ -179,7 +180,7 @@ void SupervisedUserLoginFlow::OnNewKeyAdded(
     scoped_ptr<base::DictionaryValue> password_data) {
   VLOG(1) << "New key added";
   SupervisedUserAuthentication* auth =
-      UserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
   auth->StorePasswordData(user_id(), *password_data.get());
   auth->MarkKeyIncomplete(user_id(), true /* incomplete */);
   authenticator_->RemoveKey(
@@ -224,7 +225,7 @@ void SupervisedUserLoginFlow::OnPasswordUpdated(
   VLOG(1) << "Updated password for supervised user";
 
   SupervisedUserAuthentication* auth =
-      UserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
 
   // Incomplete state is not there in password_data, carry it from old state.
   bool was_incomplete = auth->HasIncompleteKey(user_id());
@@ -248,11 +249,10 @@ void SupervisedUserLoginFlow::Finish() {
 void SupervisedUserLoginFlow::LaunchExtraSteps(
     Profile* profile) {
   profile_ = profile;
-  UserManager::Get()->GetSupervisedUserManager()->LoadSupervisedUserToken(
+  ChromeUserManager::Get()->GetSupervisedUserManager()->LoadSupervisedUserToken(
       profile,
-      base::Bind(
-           &SupervisedUserLoginFlow::OnSyncSetupDataLoaded,
-           weak_factory_.GetWeakPtr()));
+      base::Bind(&SupervisedUserLoginFlow::OnSyncSetupDataLoaded,
+                 weak_factory_.GetWeakPtr()));
 }
 
 }  // namespace chromeos
diff --git a/chrome/browser/chromeos/login/supervised/supervised_user_password_browsertest.cc b/chrome/browser/chromeos/login/supervised/supervised_user_password_browsertest.cc
index 9517059..eef1077 100644
--- a/chrome/browser/chromeos/login/supervised/supervised_user_password_browsertest.cc
+++ b/chrome/browser/chromeos/login/supervised/supervised_user_password_browsertest.cc
@@ -15,6 +15,7 @@
 #include "chrome/browser/chromeos/login/supervised/supervised_user_test_base.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_view.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
 #include "chrome/browser/chromeos/net/network_portal_detector_test_impl.h"
 #include "chrome/browser/chromeos/settings/stub_cros_settings_provider.h"
@@ -78,9 +79,10 @@ IN_PROC_BROWSER_TEST_F(SupervisedUserPasswordTest,
                        DISABLED_PRE_PasswordChangeFromUserTest) {
   SigninAsSupervisedUser(true, 0, kTestSupervisedUserDisplayName);
 
-  const user_manager::User* user = UserManager::Get()->GetUsers().at(0);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->GetUsers().at(0);
   std::string sync_id =
-      UserManager::Get()->GetSupervisedUserManager()->GetUserSyncId(
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetUserSyncId(
           user->email());
   base::DictionaryValue password;
   password.SetIntegerWithoutPathExpansion(
@@ -124,14 +126,14 @@ IN_PROC_BROWSER_TEST_F(SupervisedUserPasswordTest,
 IN_PROC_BROWSER_TEST_F(SupervisedUserPasswordTest,
                        DISABLED_PRE_PasswordChangeFromManagerTest) {
   const user_manager::User* supervised_user =
-      UserManager::Get()->GetUsers().at(0);
+      user_manager::UserManager::Get()->GetUsers().at(0);
 
   SigninAsManager(1);
 
   EXPECT_CALL(*mock_homedir_methods_, AddKeyEx(_, _, _, _, _)).Times(1);
 
   std::string sync_id =
-      UserManager::Get()->GetSupervisedUserManager()->GetUserSyncId(
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetUserSyncId(
           supervised_user->email());
 
   ::sync_pb::ManagedUserSpecifics managed_user_proto;
@@ -190,9 +192,10 @@ IN_PROC_BROWSER_TEST_F(SupervisedUserPasswordTest,
                        DISABLED_PRE_PRE_PasswordChangeUserAndManagerTest) {
   SigninAsSupervisedUser(true, 0, kTestSupervisedUserDisplayName);
 
-  const user_manager::User* user = UserManager::Get()->GetUsers().at(0);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->GetUsers().at(0);
   std::string sync_id =
-      UserManager::Get()->GetSupervisedUserManager()->GetUserSyncId(
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetUserSyncId(
           user->email());
   base::DictionaryValue password;
   password.SetIntegerWithoutPathExpansion(
@@ -213,14 +216,14 @@ IN_PROC_BROWSER_TEST_F(SupervisedUserPasswordTest,
 IN_PROC_BROWSER_TEST_F(SupervisedUserPasswordTest,
                        DISABLED_PRE_PasswordChangeUserAndManagerTest) {
   const user_manager::User* supervised_user =
-      UserManager::Get()->GetUsers().at(0);
+      user_manager::UserManager::Get()->GetUsers().at(0);
 
   SigninAsManager(1);
 
   EXPECT_CALL(*mock_homedir_methods_, AddKeyEx(_, _, _, _, _)).Times(1);
 
   std::string sync_id =
-      UserManager::Get()->GetSupervisedUserManager()->GetUserSyncId(
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetUserSyncId(
           supervised_user->email());
 
   ::sync_pb::ManagedUserSpecifics managed_user_proto;
diff --git a/chrome/browser/chromeos/login/supervised/supervised_user_test_base.cc b/chrome/browser/chromeos/login/supervised/supervised_user_test_base.cc
index fa0fc964..0074e2f 100644
--- a/chrome/browser/chromeos/login/supervised/supervised_user_test_base.cc
+++ b/chrome/browser/chromeos/login/supervised/supervised_user_test_base.cc
@@ -300,7 +300,7 @@ void SupervisedUserTestBase::StartFlowLoginAsManager() {
   login_observer.Wait();
 
   // OAuth token is valid.
-  UserManager::Get()->SaveUserOAuthStatus(
+  user_manager::UserManager::Get()->SaveUserOAuthStatus(
       kTestManager, user_manager::User::OAUTH2_TOKEN_STATUS_VALID);
   base::RunLoop().RunUntilIdle();
 
@@ -357,11 +357,11 @@ void SupervisedUserTestBase::SigninAsSupervisedUser(
     EXPECT_CALL(*mock_homedir_methods_, MountEx(_, _, _, _)).Times(1);
 
   // Log in as supervised user, make sure that everything works.
-  ASSERT_EQ(3UL, UserManager::Get()->GetUsers().size());
+  ASSERT_EQ(3UL, user_manager::UserManager::Get()->GetUsers().size());
 
   // Created supervised user have to be first in a list.
   const user_manager::User* user =
-      UserManager::Get()->GetUsers().at(user_index);
+      user_manager::UserManager::Get()->GetUsers().at(user_index);
   ASSERT_EQ(base::UTF8ToUTF16(expected_display_name), user->display_name());
   LoginUser(user->email());
   if (check_homedir_calls)
@@ -377,11 +377,11 @@ void SupervisedUserTestBase::SigninAsSupervisedUser(
 
 void SupervisedUserTestBase::SigninAsManager(int user_index) {
   // Log in as supervised user, make sure that everything works.
-  ASSERT_EQ(3UL, UserManager::Get()->GetUsers().size());
+  ASSERT_EQ(3UL, user_manager::UserManager::Get()->GetUsers().size());
 
   // Created supervised user have to be first in a list.
   const user_manager::User* user =
-      UserManager::Get()->GetUsers().at(user_index);
+      user_manager::UserManager::Get()->GetUsers().at(user_index);
   LoginUser(user->email());
   Profile* profile = ProfileHelper::Get()->GetProfileByUserUnsafe(user);
   shared_settings_adapter_.reset(
@@ -394,11 +394,12 @@ void SupervisedUserTestBase::RemoveSupervisedUser(
     int user_index,
     const std::string& expected_display_name) {
   // Remove supervised user.
-  ASSERT_EQ(original_user_count, UserManager::Get()->GetUsers().size());
+  ASSERT_EQ(original_user_count,
+            user_manager::UserManager::Get()->GetUsers().size());
 
   // Created supervised user have to be first in a list.
   const user_manager::User* user =
-      UserManager::Get()->GetUsers().at(user_index);
+      user_manager::UserManager::Get()->GetUsers().at(user_index);
   ASSERT_EQ(base::UTF8ToUTF16(expected_display_name), user->display_name());
 
   // Open pod menu.
@@ -429,7 +430,8 @@ void SupervisedUserTestBase::RemoveSupervisedUser(
       user_index));
 
   // Make sure there is no supervised user in list.
-  ASSERT_EQ(original_user_count - 1, UserManager::Get()->GetUsers().size());
+  ASSERT_EQ(original_user_count - 1,
+            user_manager::UserManager::Get()->GetUsers().size());
 }
 
 }  // namespace chromeos
diff --git a/chrome/browser/chromeos/login/ui/login_display.h b/chrome/browser/chromeos/login/ui/login_display.h
index d8e51e4..f845522 100644
--- a/chrome/browser/chromeos/login/ui/login_display.h
+++ b/chrome/browser/chromeos/login/ui/login_display.h
@@ -12,9 +12,9 @@
 #include "base/strings/string16.h"
 #include "chrome/browser/chromeos/login/help_app_launcher.h"
 #include "chrome/browser/chromeos/login/signin_specifics.h"
-#include "chrome/browser/chromeos/login/users/remove_user_delegate.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/remove_user_delegate.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "ui/gfx/image/image.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/rect.h"
@@ -25,7 +25,7 @@ class UserContext;
 
 // TODO(nkostylev): Extract interface, create a BaseLoginDisplay class.
 // An abstract class that defines login UI implementation.
-class LoginDisplay : public RemoveUserDelegate {
+class LoginDisplay : public user_manager::RemoveUserDelegate {
  public:
   // Sign in error IDs that require detailed error screen and not just
   // a simple error bubble.
diff --git a/chrome/browser/chromeos/login/ui/login_display_host_impl.cc b/chrome/browser/chromeos/login/ui/login_display_host_impl.cc
index d1d1185..f4b62fc 100644
--- a/chrome/browser/chromeos/login/ui/login_display_host_impl.cc
+++ b/chrome/browser/chromeos/login/ui/login_display_host_impl.cc
@@ -46,7 +46,6 @@
 #include "chrome/browser/chromeos/login/ui/oobe_display.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_display.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_view.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/mobile_config.h"
 #include "chrome/browser/chromeos/net/delay_network_call.h"
@@ -70,6 +69,7 @@
 #include "chromeos/login/login_state.h"
 #include "chromeos/settings/timezone_settings.h"
 #include "components/session_manager/core/session_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
 #include "content/public/browser/web_contents.h"
@@ -408,7 +408,7 @@ LoginDisplayHostImpl::~LoginDisplayHostImpl() {
 
   default_host_ = NULL;
   // TODO(tengs): This should be refactored. See crbug.com/314934.
-  if (UserManager::Get()->IsCurrentUserNew()) {
+  if (user_manager::UserManager::Get()->IsCurrentUserNew()) {
     // DriveOptInController will delete itself when finished.
     (new DriveFirstRunController(
         ProfileManager::GetActiveUserProfile()))->EnableOfflineMode();
@@ -568,7 +568,7 @@ void LoginDisplayHostImpl::StartUserAdding(
   SetOobeProgressBarVisible(oobe_progress_bar_visible_ = false);
   SetStatusAreaVisible(true);
   sign_in_controller_->Init(
-      chromeos::UserManager::Get()->GetUsersAdmittedForMultiProfile());
+      user_manager::UserManager::Get()->GetUsersAdmittedForMultiProfile());
   CHECK(webui_login_display_);
   GetOobeUI()->ShowSigninScreen(LoginScreenContext(),
                                 webui_login_display_,
@@ -605,7 +605,7 @@ void LoginDisplayHostImpl::StartSignInScreen(
 
   DVLOG(1) << "Starting sign in screen";
   const user_manager::UserList& users =
-      chromeos::UserManager::Get()->GetUsers();
+      user_manager::UserManager::Get()->GetUsers();
 
   // Fix for users who updated device and thus never passed register screen.
   // If we already have users, we assume that it is not a second part of
@@ -777,7 +777,7 @@ void LoginDisplayHostImpl::Observe(
                       chrome::NOTIFICATION_BROWSER_OPENED,
                       content::NotificationService::AllSources());
   } else if (type == chrome::NOTIFICATION_LOGIN_USER_CHANGED &&
-             chromeos::UserManager::Get()->IsCurrentUserNew()) {
+             user_manager::UserManager::Get()->IsCurrentUserNew()) {
     // For new user, move desktop to locker container so that windows created
     // during the user image picker step are below it.
     ash::Shell::GetInstance()->
diff --git a/chrome/browser/chromeos/login/ui/user_adding_screen.cc b/chrome/browser/chromeos/login/ui/user_adding_screen.cc
index 8547d7b..e74b072 100644
--- a/chrome/browser/chromeos/login/ui/user_adding_screen.cc
+++ b/chrome/browser/chromeos/login/ui/user_adding_screen.cc
@@ -14,6 +14,7 @@
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "components/session_manager/core/session_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/size.h"
 
@@ -64,9 +65,9 @@ void UserAddingScreenImpl::Cancel() {
   display_host_->Finalize();
 
   // Reset wallpaper if cancel adding user from multiple user sign in page.
-  if (UserManager::Get()->IsUserLoggedIn()) {
+  if (user_manager::UserManager::Get()->IsUserLoggedIn()) {
     WallpaperManager::Get()->SetUserWallpaperDelayed(
-        UserManager::Get()->GetActiveUser()->email());
+        user_manager::UserManager::Get()->GetActiveUser()->email());
   }
 }
 
diff --git a/chrome/browser/chromeos/login/ui/user_adding_screen_browsertest.cc b/chrome/browser/chromeos/login/ui/user_adding_screen_browsertest.cc
index 94771ba..a1e1174 100644
--- a/chrome/browser/chromeos/login/ui/user_adding_screen_browsertest.cc
+++ b/chrome/browser/chromeos/login/ui/user_adding_screen_browsertest.cc
@@ -14,10 +14,10 @@
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_view.h"
 #include "chrome/browser/chromeos/login/users/multi_profile_user_controller.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/in_process_browser_test.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/test/test_utils.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -92,15 +92,15 @@ IN_PROC_BROWSER_TEST_F(UserAddingScreenTest, PRE_CancelAdding) {
 
 IN_PROC_BROWSER_TEST_F(UserAddingScreenTest, CancelAdding) {
   EXPECT_CALL(login_utils(), DoBrowserLaunch(_, _)).Times(1);
-  EXPECT_EQ(3u, UserManager::Get()->GetUsers().size());
-  EXPECT_EQ(0u, UserManager::Get()->GetLoggedInUsers().size());
+  EXPECT_EQ(3u, user_manager::UserManager::Get()->GetUsers().size());
+  EXPECT_EQ(0u, user_manager::UserManager::Get()->GetLoggedInUsers().size());
 
   EXPECT_EQ(ash::SessionStateDelegate::SESSION_STATE_LOGIN_PRIMARY,
             ash::Shell::GetInstance()->session_state_delegate()->
                 GetSessionState());
 
   LoginUser(kTestUsers[0]);
-  EXPECT_EQ(1u, UserManager::Get()->GetLoggedInUsers().size());
+  EXPECT_EQ(1u, user_manager::UserManager::Get()->GetLoggedInUsers().size());
   EXPECT_EQ(ash::SessionStateDelegate::SESSION_STATE_ACTIVE,
             ash::Shell::GetInstance()->session_state_delegate()->
                 GetSessionState());
@@ -120,8 +120,9 @@ IN_PROC_BROWSER_TEST_F(UserAddingScreenTest, CancelAdding) {
                 GetSessionState());
 
   EXPECT_TRUE(LoginDisplayHostImpl::default_host() == NULL);
-  EXPECT_EQ(1u, UserManager::Get()->GetLoggedInUsers().size());
-  EXPECT_EQ(kTestUsers[0], UserManager::Get()->GetActiveUser()->email());
+  EXPECT_EQ(1u, user_manager::UserManager::Get()->GetLoggedInUsers().size());
+  EXPECT_EQ(kTestUsers[0],
+            user_manager::UserManager::Get()->GetActiveUser()->email());
 }
 
 IN_PROC_BROWSER_TEST_F(UserAddingScreenTest, PRE_AddingSeveralUsers) {
@@ -141,7 +142,7 @@ IN_PROC_BROWSER_TEST_F(UserAddingScreenTest, AddingSeveralUsers) {
             ash::Shell::GetInstance()->session_state_delegate()->
                 GetSessionState());
 
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
   for (int i = 1; i < 3; ++i) {
     UserAddingScreen::Get()->Start();
diff --git a/chrome/browser/chromeos/login/ui/webui_login_display.cc b/chrome/browser/chromeos/login/ui/webui_login_display.cc
index f7a12e7..ececc37 100644
--- a/chrome/browser/chromeos/login/ui/webui_login_display.cc
+++ b/chrome/browser/chromeos/login/ui/webui_login_display.cc
@@ -19,6 +19,7 @@
 #include "chromeos/ime/ime_keyboard.h"
 #include "chromeos/ime/input_method_manager.h"
 #include "chromeos/login/user_names.h"
+#include "components/user_manager/user_manager.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/views/widget/widget.h"
 #include "ui/wm/core/user_activity_detector.h"
@@ -122,7 +123,7 @@ void WebUILoginDisplay::SetUIEnabled(bool is_enabled) {
   // Allow this call only before user sign in or at lock screen.
   // If this call is made after new user signs in but login screen is still
   // around that would trigger a sign in extension refresh.
-  if (is_enabled && (!UserManager::Get()->IsUserLoggedIn() ||
+  if (is_enabled && (!user_manager::UserManager::Get()->IsUserLoggedIn() ||
                      ScreenLocker::default_screen_locker())) {
     ClearAndEnablePassword();
   }
@@ -277,7 +278,7 @@ void WebUILoginDisplay::OnSigninScreenReady() {
 }
 
 void WebUILoginDisplay::RemoveUser(const std::string& username) {
-  UserManager::Get()->RemoveUser(username, this);
+  user_manager::UserManager::Get()->RemoveUser(username, this);
 }
 
 void WebUILoginDisplay::ResyncUserData() {
diff --git a/chrome/browser/chromeos/login/user_flow.cc b/chrome/browser/chromeos/login/user_flow.cc
index 81fe9908..fcfc9ca 100644
--- a/chrome/browser/chromeos/login/user_flow.cc
+++ b/chrome/browser/chromeos/login/user_flow.cc
@@ -5,14 +5,14 @@
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
 #include "chrome/browser/chromeos/login/user_flow.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 
 namespace chromeos {
 
 namespace {
 
 void UnregisterFlow(const std::string& user_id) {
-  UserManager::Get()->ResetUserFlow(user_id);
+  ChromeUserManager::Get()->ResetUserFlow(user_id);
 }
 
 } // namespace
diff --git a/chrome/browser/chromeos/login/users/avatar/user_image_manager_browsertest.cc b/chrome/browser/chromeos/login/users/avatar/user_image_manager_browsertest.cc
index 146130e..46a772b 100644
--- a/chrome/browser/chromeos/login/users/avatar/user_image_manager_browsertest.cc
+++ b/chrome/browser/chromeos/login/users/avatar/user_image_manager_browsertest.cc
@@ -30,8 +30,9 @@
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager_test_util.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/policy/cloud_external_data_manager_base_test_util.h"
 #include "chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos.h"
 #include "chrome/browser/chromeos/policy/user_cloud_policy_manager_factory_chromeos.h"
@@ -53,6 +54,7 @@
 #include "components/user_manager/user.h"
 #include "components/user_manager/user_image/default_user_images.h"
 #include "components/user_manager/user_image/user_image.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_source.h"
 #include "content/public/test/test_utils.h"
@@ -96,7 +98,7 @@ policy::CloudPolicyStore* GetStoreForUser(const user_manager::User* user) {
 }  // namespace
 
 class UserImageManagerTest : public LoginManagerTest,
-                             public UserManager::Observer {
+                             public user_manager::UserManager::Observer {
  protected:
   UserImageManagerTest() : LoginManagerTest(true) {
   }
@@ -112,23 +114,24 @@ class UserImageManagerTest : public LoginManagerTest,
   virtual void SetUpOnMainThread() OVERRIDE {
     LoginManagerTest::SetUpOnMainThread();
     local_state_ = g_browser_process->local_state();
-    UserManager::Get()->AddObserver(this);
+    user_manager::UserManager::Get()->AddObserver(this);
   }
 
   virtual void TearDownOnMainThread() OVERRIDE {
-    UserManager::Get()->RemoveObserver(this);
+    user_manager::UserManager::Get()->RemoveObserver(this);
     LoginManagerTest::TearDownOnMainThread();
   }
 
   // UserManager::Observer overrides:
-  virtual void LocalStateChanged(UserManager* user_manager) OVERRIDE {
+  virtual void LocalStateChanged(
+      user_manager::UserManager* user_manager) OVERRIDE {
     if (run_loop_)
       run_loop_->Quit();
   }
 
   // Logs in |username|.
   void LogIn(const std::string& username) {
-    UserManager::Get()->UserLoggedIn(username, username, false);
+    user_manager::UserManager::Get()->UserLoggedIn(username, username, false);
   }
 
   // Stores old (pre-migration) user image info.
@@ -225,8 +228,8 @@ class UserImageManagerTest : public LoginManagerTest,
       net::TestURLFetcherFactory* url_fetcher_factory) {
     ProfileDownloader* profile_downloader =
         reinterpret_cast<UserImageManagerImpl*>(
-            UserManager::Get()->GetUserImageManager(username))->
-                profile_downloader_.get();
+            ChromeUserManager::Get()->GetUserImageManager(username))
+            ->profile_downloader_.get();
     ASSERT_TRUE(profile_downloader);
 
     static_cast<OAuth2TokenService::Consumer*>(profile_downloader)->
@@ -274,10 +277,11 @@ class UserImageManagerTest : public LoginManagerTest,
     fetcher->delegate()->OnURLFetchComplete(fetcher);
     run_loop.Run();
 
-    const user_manager::User* user = UserManager::Get()->GetLoggedInUser();
+    const user_manager::User* user =
+        user_manager::UserManager::Get()->GetLoggedInUser();
     ASSERT_TRUE(user);
     UserImageManagerImpl* uim = reinterpret_cast<UserImageManagerImpl*>(
-        UserManager::Get()->GetUserImageManager(user->email()));
+        ChromeUserManager::Get()->GetUserImageManager(user->email()));
     if (uim->job_.get()) {
       run_loop_.reset(new base::RunLoop);
       run_loop_->Run();
@@ -305,7 +309,7 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, PRE_DefaultUserImagePreserved) {
 }
 
 IN_PROC_BROWSER_TEST_F(UserImageManagerTest, DefaultUserImagePreserved) {
-  UserManager::Get()->GetUsers();  // Load users.
+  user_manager::UserManager::Get()->GetUsers();  // Load users.
   // Old info preserved.
   ExpectOldUserImageInfo(
       kTestUser1, user_manager::kFirstDefaultImageIndex, base::FilePath());
@@ -325,7 +329,7 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, PRE_OtherUsersUnaffected) {
 }
 
 IN_PROC_BROWSER_TEST_F(UserImageManagerTest, OtherUsersUnaffected) {
-  UserManager::Get()->GetUsers();  // Load users.
+  user_manager::UserManager::Get()->GetUsers();  // Load users.
   // Old info preserved.
   ExpectOldUserImageInfo(
       kTestUser1, user_manager::kFirstDefaultImageIndex, base::FilePath());
@@ -348,12 +352,13 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, PRE_PRE_NonJPEGImageFromFile) {
 }
 
 IN_PROC_BROWSER_TEST_F(UserImageManagerTest, PRE_NonJPEGImageFromFile) {
-  UserManager::Get()->GetUsers();  // Load users.
+  user_manager::UserManager::Get()->GetUsers();  // Load users.
   // Old info preserved.
   ExpectOldUserImageInfo(kTestUser1,
                          user_manager::User::USER_IMAGE_EXTERNAL,
                          GetUserImagePath(kTestUser1, "png"));
-  const user_manager::User* user = UserManager::Get()->FindUser(kTestUser1);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   EXPECT_TRUE(user->image_is_stub());
 
   base::RunLoop run_loop;
@@ -369,7 +374,7 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, PRE_NonJPEGImageFromFile) {
   ExpectNewUserImageInfo(kTestUser1,
                          user_manager::User::USER_IMAGE_EXTERNAL,
                          GetUserImagePath(kTestUser1, "jpg"));
-  user = UserManager::Get()->GetLoggedInUser();
+  user = user_manager::UserManager::Get()->GetLoggedInUser();
   ASSERT_TRUE(user);
   EXPECT_FALSE(user->image_is_safe_format());
   // Check image dimensions.
@@ -380,8 +385,9 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, PRE_NonJPEGImageFromFile) {
 }
 
 IN_PROC_BROWSER_TEST_F(UserImageManagerTest, NonJPEGImageFromFile) {
-  UserManager::Get()->GetUsers();  // Load users.
-  const user_manager::User* user = UserManager::Get()->FindUser(kTestUser1);
+  user_manager::UserManager::Get()->GetUsers();  // Load users.
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   ASSERT_TRUE(user);
   // Wait for image load.
   if (user->image_index() == user_manager::User::USER_IMAGE_INVALID) {
@@ -405,14 +411,15 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, PRE_SaveUserDefaultImageIndex) {
 // Verifies that SaveUserDefaultImageIndex() correctly sets and persists the
 // chosen user image.
 IN_PROC_BROWSER_TEST_F(UserImageManagerTest, SaveUserDefaultImageIndex) {
-  const user_manager::User* user = UserManager::Get()->FindUser(kTestUser1);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   ASSERT_TRUE(user);
 
   const gfx::ImageSkia& default_image =
       user_manager::GetDefaultImage(user_manager::kFirstDefaultImageIndex);
 
   UserImageManager* user_image_manager =
-      UserManager::Get()->GetUserImageManager(kTestUser1);
+      ChromeUserManager::Get()->GetUserImageManager(kTestUser1);
   user_image_manager->SaveUserDefaultImageIndex(
       user_manager::kFirstDefaultImageIndex);
 
@@ -430,7 +437,8 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, PRE_SaveUserImage) {
 // Verifies that SaveUserImage() correctly sets and persists the chosen user
 // image.
 IN_PROC_BROWSER_TEST_F(UserImageManagerTest, SaveUserImage) {
-  const user_manager::User* user = UserManager::Get()->FindUser(kTestUser1);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   ASSERT_TRUE(user);
 
   SkBitmap custom_image_bitmap;
@@ -441,7 +449,7 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, SaveUserImage) {
 
   run_loop_.reset(new base::RunLoop);
   UserImageManager* user_image_manager =
-      UserManager::Get()->GetUserImageManager(kTestUser1);
+      ChromeUserManager::Get()->GetUserImageManager(kTestUser1);
   user_image_manager->SaveUserImage(
       user_manager::UserImage::CreateAndEncode(custom_image));
   run_loop_->Run();
@@ -469,7 +477,8 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, PRE_SaveUserImageFromFile) {
 // Verifies that SaveUserImageFromFile() correctly sets and persists the chosen
 // user image.
 IN_PROC_BROWSER_TEST_F(UserImageManagerTest, SaveUserImageFromFile) {
-  const user_manager::User* user = UserManager::Get()->FindUser(kTestUser1);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   ASSERT_TRUE(user);
 
   const base::FilePath custom_image_path =
@@ -480,7 +489,7 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, SaveUserImageFromFile) {
 
   run_loop_.reset(new base::RunLoop);
   UserImageManager* user_image_manager =
-      UserManager::Get()->GetUserImageManager(kTestUser1);
+      ChromeUserManager::Get()->GetUserImageManager(kTestUser1);
   user_image_manager->SaveUserImageFromFile(custom_image_path);
   run_loop_->Run();
 
@@ -509,7 +518,8 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest,
 // Verifies that SaveUserImageFromProfileImage() correctly downloads, sets and
 // persists the chosen user image.
 IN_PROC_BROWSER_TEST_F(UserImageManagerTest, SaveUserImageFromProfileImage) {
-  const user_manager::User* user = UserManager::Get()->FindUser(kTestUser1);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   ASSERT_TRUE(user);
 
   UserImageManagerImpl::IgnoreProfileDataDownloadDelayForTesting();
@@ -517,7 +527,7 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest, SaveUserImageFromProfileImage) {
 
   run_loop_.reset(new base::RunLoop);
   UserImageManager* user_image_manager =
-      UserManager::Get()->GetUserImageManager(kTestUser1);
+      ChromeUserManager::Get()->GetUserImageManager(kTestUser1);
   user_image_manager->SaveUserImageFromProfileImage();
   run_loop_->Run();
 
@@ -556,7 +566,8 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest,
 // clobber the default image chosen in the meantime.
 IN_PROC_BROWSER_TEST_F(UserImageManagerTest,
                        ProfileImageDownloadDoesNotClobber) {
-  const user_manager::User* user = UserManager::Get()->FindUser(kTestUser1);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   ASSERT_TRUE(user);
 
   const gfx::ImageSkia& default_image =
@@ -567,7 +578,7 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerTest,
 
   run_loop_.reset(new base::RunLoop);
   UserImageManager* user_image_manager =
-      UserManager::Get()->GetUserImageManager(kTestUser1);
+      ChromeUserManager::Get()->GetUserImageManager(kTestUser1);
   user_image_manager->SaveUserImageFromProfileImage();
   run_loop_->Run();
 
@@ -676,7 +687,8 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerPolicyTest, PRE_SetAndClear) {
 // image.
 // http://crbug.com/396352
 IN_PROC_BROWSER_TEST_F(UserImageManagerPolicyTest, DISABLED_SetAndClear) {
-  const user_manager::User* user = UserManager::Get()->FindUser(kTestUser1);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   ASSERT_TRUE(user);
 
   LoginUser(kTestUser1);
@@ -745,7 +757,7 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerPolicyTest, DISABLED_SetAndClear) {
       user_manager::GetDefaultImage(user_image_index);
 
   UserImageManager* user_image_manager =
-      UserManager::Get()->GetUserImageManager(kTestUser1);
+      ChromeUserManager::Get()->GetUserImageManager(kTestUser1);
   user_image_manager->SaveUserDefaultImageIndex(user_image_index);
 
   EXPECT_TRUE(user->HasDefaultImage());
@@ -763,7 +775,8 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerPolicyTest, PRE_PolicyOverridesUser) {
 // then set through policy, the policy takes precedence, overriding the
 // previously chosen image.
 IN_PROC_BROWSER_TEST_F(UserImageManagerPolicyTest, PolicyOverridesUser) {
-  const user_manager::User* user = UserManager::Get()->FindUser(kTestUser1);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   ASSERT_TRUE(user);
 
   LoginUser(kTestUser1);
@@ -778,7 +791,7 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerPolicyTest, PolicyOverridesUser) {
       user_manager::GetDefaultImage(user_manager::kFirstDefaultImageIndex);
 
   UserImageManager* user_image_manager =
-      UserManager::Get()->GetUserImageManager(kTestUser1);
+      ChromeUserManager::Get()->GetUserImageManager(kTestUser1);
   user_image_manager->SaveUserDefaultImageIndex(
       user_manager::kFirstDefaultImageIndex);
 
@@ -825,7 +838,8 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerPolicyTest,
 // chooses a different image, the policy takes precedence, preventing the user
 // from overriding the previously chosen image.
 IN_PROC_BROWSER_TEST_F(UserImageManagerPolicyTest, UserDoesNotOverridePolicy) {
-  const user_manager::User* user = UserManager::Get()->FindUser(kTestUser1);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   ASSERT_TRUE(user);
 
   LoginUser(kTestUser1);
@@ -863,7 +877,7 @@ IN_PROC_BROWSER_TEST_F(UserImageManagerPolicyTest, UserDoesNotOverridePolicy) {
   // Choose a different user image. Verify that the user image does not change
   // as policy takes precedence.
   UserImageManager* user_image_manager =
-      UserManager::Get()->GetUserImageManager(kTestUser1);
+      ChromeUserManager::Get()->GetUserImageManager(kTestUser1);
   user_image_manager->SaveUserDefaultImageIndex(
       user_manager::kFirstDefaultImageIndex);
 
diff --git a/chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.cc b/chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.cc
index f54185a..b112818 100644
--- a/chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.cc
+++ b/chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.cc
@@ -25,7 +25,6 @@
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/helper.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_sync_observer.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile_downloader.h"
 #include "chrome/browser/profiles/profile_manager.h"
@@ -33,6 +32,7 @@
 #include "chrome/grit/theme_resources.h"
 #include "components/user_manager/user_image/default_user_images.h"
 #include "components/user_manager/user_image/user_image.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
@@ -470,8 +470,9 @@ void UserImageManagerImpl::Job::NotifyJobDone() {
   parent_->OnJobDone();
 }
 
-UserImageManagerImpl::UserImageManagerImpl(const std::string& user_id,
-                                           UserManager* user_manager)
+UserImageManagerImpl::UserImageManagerImpl(
+    const std::string& user_id,
+    user_manager::UserManager* user_manager)
     : UserImageManager(user_id),
       user_manager_(user_manager),
       downloading_profile_image_(false),
@@ -763,9 +764,10 @@ void UserImageManagerImpl::OnProfileDownloadSuccess(
 
   user_manager_->UpdateUserAccountData(
       user_id(),
-      UserManager::UserAccountData(downloader->GetProfileFullName(),
-                                   downloader->GetProfileGivenName(),
-                                   downloader->GetProfileLocale()));
+      user_manager::UserManager::UserAccountData(
+          downloader->GetProfileFullName(),
+          downloader->GetProfileGivenName(),
+          downloader->GetProfileLocale()));
   if (!downloading_profile_image_)
     return;
 
diff --git a/chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.h b/chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.h
index 1f4b8b0..7390374 100644
--- a/chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.h
+++ b/chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.h
@@ -32,12 +32,12 @@ class SequencedTaskRunner;
 
 namespace user_manager {
 class UserImage;
+class UserManager;
 }
 
 namespace chromeos {
 
 class UserImageSyncObserver;
-class UserManager;
 
 class UserImageManagerImpl
     : public UserImageManager,
@@ -45,7 +45,7 @@ class UserImageManagerImpl
  public:
   // UserImageManager:
   UserImageManagerImpl(const std::string& user_id,
-                       UserManager* user_manager);
+                       user_manager::UserManager* user_manager);
   virtual ~UserImageManagerImpl();
 
   virtual void LoadUserImage() OVERRIDE;
@@ -153,7 +153,7 @@ class UserImageManagerImpl
   bool IsUserLoggedInAndRegular() const;
 
   // The user manager.
-  UserManager* user_manager_;
+  user_manager::UserManager* user_manager_;
 
   // Loader for JPEG user images.
   scoped_refptr<UserImageLoader> image_loader_;
diff --git a/chrome/browser/chromeos/login/users/avatar/user_image_sync_observer.cc b/chrome/browser/chromeos/login/users/avatar/user_image_sync_observer.cc
index bb9268f..0052395 100644
--- a/chrome/browser/chromeos/login/users/avatar/user_image_sync_observer.cc
+++ b/chrome/browser/chromeos/login/users/avatar/user_image_sync_observer.cc
@@ -10,12 +10,14 @@
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/screens/user_image_screen.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/prefs/pref_service_syncable.h"
 #include "chrome/common/pref_names.h"
 #include "components/user_manager/user.h"
 #include "components/user_manager/user_image/default_user_images.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/notification_service.h"
 
@@ -168,7 +170,7 @@ void UserImageSyncObserver::UpdateLocalImageFromSynced() {
   if ((synced_index == local_index) || !IsIndexSupported(synced_index))
     return;
   UserImageManager* image_manager =
-      UserManager::Get()->GetUserImageManager(user_->email());
+      ChromeUserManager::Get()->GetUserImageManager(user_->email());
   if (synced_index == user_manager::User::USER_IMAGE_PROFILE) {
     image_manager->SaveUserImageFromProfileImage();
   } else {
diff --git a/chrome/browser/chromeos/login/users/avatar/user_image_sync_observer.h b/chrome/browser/chromeos/login/users/avatar/user_image_sync_observer.h
index 503338b..a4c82ca 100644
--- a/chrome/browser/chromeos/login/users/avatar/user_image_sync_observer.h
+++ b/chrome/browser/chromeos/login/users/avatar/user_image_sync_observer.h
@@ -9,16 +9,13 @@
 
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/prefs/pref_service_syncable_observer.h"
 #include "content/public/browser/notification_observer.h"
 
 class PrefChangeRegistrar;
 class PrefServiceSyncable;
 class Profile;
-namespace chromeos {
-class User;
-}
+
 namespace content {
 class NotificationRegistrar;
 }
@@ -26,6 +23,10 @@ namespace user_prefs {
 class PrefRegistrySyncable;
 }
 
+namespace user_manager {
+class User;
+}
+
 namespace chromeos {
 
 // This class is responsible for keeping local user image synced with
diff --git a/chrome/browser/chromeos/login/users/chrome_user_manager.cc b/chrome/browser/chromeos/login/users/chrome_user_manager.cc
index d7fdd8b..1800e30 100644
--- a/chrome/browser/chromeos/login/users/chrome_user_manager.cc
+++ b/chrome/browser/chromeos/login/users/chrome_user_manager.cc
@@ -3,1016 +3,23 @@
 // found in the LICENSE file.
 
 #include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
-
-#include <cstddef>
-#include <set>
-
-#include "ash/multi_profile_uma.h"
-#include "base/bind.h"
-#include "base/bind_helpers.h"
-#include "base/command_line.h"
-#include "base/compiler_specific.h"
-#include "base/format_macros.h"
-#include "base/logging.h"
-#include "base/metrics/histogram.h"
-#include "base/prefs/pref_registry_simple.h"
-#include "base/prefs/pref_service.h"
-#include "base/prefs/scoped_user_pref_update.h"
-#include "base/strings/string_util.h"
-#include "base/strings/stringprintf.h"
-#include "base/strings/utf_string_conversions.h"
-#include "base/values.h"
-#include "chrome/browser/browser_process.h"
-#include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/chromeos/login/demo_mode/demo_app_launcher.h"
-#include "chrome/browser/chromeos/login/session/user_session_manager.h"
-#include "chrome/browser/chromeos/login/signin/auth_sync_observer.h"
-#include "chrome/browser/chromeos/login/signin/auth_sync_observer_factory.h"
-#include "chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.h"
-#include "chrome/browser/chromeos/login/users/multi_profile_user_controller.h"
-#include "chrome/browser/chromeos/login/users/remove_user_delegate.h"
-#include "chrome/browser/chromeos/login/users/supervised_user_manager_impl.h"
-#include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
-#include "chrome/browser/chromeos/policy/device_local_account.h"
-#include "chrome/browser/chromeos/profiles/multiprofiles_session_aborted_dialog.h"
-#include "chrome/browser/chromeos/profiles/profile_helper.h"
-#include "chrome/browser/chromeos/session_length_limiter.h"
-#include "chrome/browser/profiles/profile.h"
-#include "chrome/browser/supervised_user/chromeos/manager_password_service_factory.h"
-#include "chrome/browser/supervised_user/chromeos/supervised_user_password_service_factory.h"
-#include "chrome/common/chrome_constants.h"
-#include "chrome/common/chrome_switches.h"
-#include "chrome/common/crash_keys.h"
-#include "chrome/common/pref_names.h"
-#include "chrome/grit/theme_resources.h"
-#include "chromeos/chromeos_switches.h"
-#include "chromeos/login/user_names.h"
-#include "chromeos/settings/cros_settings_names.h"
-#include "components/session_manager/core/session_manager.h"
-#include "components/user_manager/user_image/user_image.h"
-#include "components/user_manager/user_type.h"
-#include "content/public/browser/browser_thread.h"
-#include "content/public/browser/notification_service.h"
-#include "policy/policy_constants.h"
-#include "ui/base/resource/resource_bundle.h"
-#include "ui/wm/core/wm_core_switches.h"
-
-using content::BrowserThread;
+#include "components/user_manager/user_manager.h"
 
 namespace chromeos {
-namespace {
-
-// A vector pref of the the regular users known on this device, arranged in LRU
-// order.
-const char kRegularUsers[] = "LoggedInUsers";
-
-// A vector pref of the public accounts defined on this device.
-const char kPublicAccounts[] = "PublicAccounts";
-
-// A string pref that gets set when a public account is removed but a user is
-// currently logged into that account, requiring the account's data to be
-// removed after logout.
-const char kPublicAccountPendingDataRemoval[] =
-    "PublicAccountPendingDataRemoval";
-
-}  // namespace
 
-// static
-void UserManager::RegisterPrefs(PrefRegistrySimple* registry) {
-  UserManagerBase::RegisterPrefs(registry);
-
-  registry->RegisterListPref(kPublicAccounts);
-  registry->RegisterStringPref(kPublicAccountPendingDataRemoval, std::string());
-  SupervisedUserManager::RegisterPrefs(registry);
-  SessionLengthLimiter::RegisterPrefs(registry);
-}
-
-ChromeUserManager::ChromeUserManager()
-    : cros_settings_(CrosSettings::Get()),
-      device_local_account_policy_service_(NULL),
-      supervised_user_manager_(new SupervisedUserManagerImpl(this)),
-      weak_factory_(this) {
-  UpdateNumberOfUsers();
-
-  // UserManager instance should be used only on UI thread.
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  registrar_.Add(this,
-                 chrome::NOTIFICATION_OWNERSHIP_STATUS_CHANGED,
-                 content::NotificationService::AllSources());
-  registrar_.Add(this,
-                 chrome::NOTIFICATION_LOGIN_USER_PROFILE_PREPARED,
-                 content::NotificationService::AllSources());
-  registrar_.Add(this,
-                 chrome::NOTIFICATION_PROFILE_CREATED,
-                 content::NotificationService::AllSources());
-
-  // Since we're in ctor postpone any actions till this is fully created.
-  if (base::MessageLoop::current()) {
-    base::MessageLoop::current()->PostTask(
-        FROM_HERE,
-        base::Bind(&ChromeUserManager::RetrieveTrustedDevicePolicies,
-                   weak_factory_.GetWeakPtr()));
-  }
-
-  local_accounts_subscription_ = cros_settings_->AddSettingsObserver(
-      kAccountsPrefDeviceLocalAccounts,
-      base::Bind(&ChromeUserManager::RetrieveTrustedDevicePolicies,
-                 weak_factory_.GetWeakPtr()));
-  multi_profile_user_controller_.reset(
-      new MultiProfileUserController(this, GetLocalState()));
-
-  policy::BrowserPolicyConnectorChromeOS* connector =
-      g_browser_process->platform_part()->browser_policy_connector_chromeos();
-  avatar_policy_observer_.reset(new policy::CloudExternalDataPolicyObserver(
-      cros_settings_,
-      connector->GetDeviceLocalAccountPolicyService(),
-      policy::key::kUserAvatarImage,
-      this));
-  avatar_policy_observer_->Init();
-
-  wallpaper_policy_observer_.reset(new policy::CloudExternalDataPolicyObserver(
-      cros_settings_,
-      connector->GetDeviceLocalAccountPolicyService(),
-      policy::key::kWallpaperImage,
-      this));
-  wallpaper_policy_observer_->Init();
+ChromeUserManager::ChromeUserManager(
+    scoped_refptr<base::TaskRunner> task_runner,
+    scoped_refptr<base::TaskRunner> blocking_task_runner)
+    : UserManagerBase(task_runner, blocking_task_runner) {
 }
 
 ChromeUserManager::~ChromeUserManager() {
 }
 
-void ChromeUserManager::Shutdown() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  UserManagerBase::Shutdown();
-
-  local_accounts_subscription_.reset();
-
-  // Stop the session length limiter.
-  session_length_limiter_.reset();
-
-  if (device_local_account_policy_service_)
-    device_local_account_policy_service_->RemoveObserver(this);
-
-  for (UserImageManagerMap::iterator it = user_image_managers_.begin(),
-                                     ie = user_image_managers_.end();
-       it != ie;
-       ++it) {
-    it->second->Shutdown();
-  }
-  multi_profile_user_controller_.reset();
-  avatar_policy_observer_.reset();
-  wallpaper_policy_observer_.reset();
-  registrar_.RemoveAll();
-}
-
-MultiProfileUserController* ChromeUserManager::GetMultiProfileUserController() {
-  return multi_profile_user_controller_.get();
-}
-
-UserImageManager* ChromeUserManager::GetUserImageManager(
-    const std::string& user_id) {
-  UserImageManagerMap::iterator ui = user_image_managers_.find(user_id);
-  if (ui != user_image_managers_.end())
-    return ui->second.get();
-  linked_ptr<UserImageManagerImpl> mgr(new UserImageManagerImpl(user_id, this));
-  user_image_managers_[user_id] = mgr;
-  return mgr.get();
-}
-
-SupervisedUserManager* ChromeUserManager::GetSupervisedUserManager() {
-  return supervised_user_manager_.get();
-}
-
-user_manager::UserList ChromeUserManager::GetUsersAdmittedForMultiProfile()
-    const {
-  // Supervised users are not allowed to use multi-profiles.
-  if (GetLoggedInUsers().size() == 1 &&
-      GetPrimaryUser()->GetType() != user_manager::USER_TYPE_REGULAR) {
-    return user_manager::UserList();
-  }
-
-  user_manager::UserList result;
-  const user_manager::UserList& users = GetUsers();
-  for (user_manager::UserList::const_iterator it = users.begin();
-       it != users.end();
-       ++it) {
-    if ((*it)->GetType() == user_manager::USER_TYPE_REGULAR &&
-        !(*it)->is_logged_in()) {
-      MultiProfileUserController::UserAllowedInSessionReason check;
-      multi_profile_user_controller_->IsUserAllowedInSession((*it)->email(),
-                                                             &check);
-      if (check ==
-          MultiProfileUserController::NOT_ALLOWED_PRIMARY_USER_POLICY_FORBIDS) {
-        return user_manager::UserList();
-      }
-
-      // Users with a policy that prevents them being added to a session will be
-      // shown in login UI but will be grayed out.
-      // Same applies to owner account (see http://crbug.com/385034).
-      if (check == MultiProfileUserController::ALLOWED ||
-          check == MultiProfileUserController::NOT_ALLOWED_POLICY_FORBIDS ||
-          check == MultiProfileUserController::NOT_ALLOWED_OWNER_AS_SECONDARY ||
-          check ==
-              MultiProfileUserController::NOT_ALLOWED_POLICY_CERT_TAINTED) {
-        result.push_back(*it);
-      }
-    }
-  }
-
-  return result;
-}
-
-user_manager::UserList ChromeUserManager::GetUnlockUsers() const {
-  const user_manager::UserList& logged_in_users = GetLoggedInUsers();
-  if (logged_in_users.empty())
-    return user_manager::UserList();
-
-  user_manager::UserList unlock_users;
-  Profile* profile =
-      ProfileHelper::Get()->GetProfileByUserUnsafe(GetPrimaryUser());
-  std::string primary_behavior =
-      profile->GetPrefs()->GetString(prefs::kMultiProfileUserBehavior);
-
-  // Specific case: only one logged in user or
-  // primary user has primary-only multi-profile policy.
-  if (logged_in_users.size() == 1 ||
-      primary_behavior == MultiProfileUserController::kBehaviorPrimaryOnly) {
-    if (GetPrimaryUser()->can_lock())
-      unlock_users.push_back(primary_user_);
-  } else {
-    // Fill list of potential unlock users based on multi-profile policy state.
-    for (user_manager::UserList::const_iterator it = logged_in_users.begin();
-         it != logged_in_users.end();
-         ++it) {
-      user_manager::User* user = (*it);
-      Profile* profile = ProfileHelper::Get()->GetProfileByUserUnsafe(user);
-      const std::string behavior =
-          profile->GetPrefs()->GetString(prefs::kMultiProfileUserBehavior);
-      if (behavior == MultiProfileUserController::kBehaviorUnrestricted &&
-          user->can_lock()) {
-        unlock_users.push_back(user);
-      } else if (behavior == MultiProfileUserController::kBehaviorPrimaryOnly) {
-        NOTREACHED()
-            << "Spotted primary-only multi-profile policy for non-primary user";
-      }
-    }
-  }
-
-  return unlock_users;
-}
-
-void ChromeUserManager::SessionStarted() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  UserManagerBase::SessionStarted();
-
-  content::NotificationService::current()->Notify(
-      chrome::NOTIFICATION_SESSION_STARTED,
-      content::Source<UserManager>(this),
-      content::Details<const user_manager::User>(GetActiveUser()));
-}
-
-void ChromeUserManager::RemoveUserInternal(const std::string& user_email,
-                                           RemoveUserDelegate* delegate) {
-  CrosSettings* cros_settings = CrosSettings::Get();
-
-  const base::Closure& callback =
-      base::Bind(&ChromeUserManager::RemoveUserInternal,
-                 weak_factory_.GetWeakPtr(),
-                 user_email,
-                 delegate);
-
-  // Ensure the value of owner email has been fetched.
-  if (CrosSettingsProvider::TRUSTED !=
-      cros_settings->PrepareTrustedValues(callback)) {
-    // Value of owner email is not fetched yet.  RemoveUserInternal will be
-    // called again after fetch completion.
-    return;
-  }
-  std::string owner;
-  cros_settings->GetString(kDeviceOwner, &owner);
-  if (user_email == owner) {
-    // Owner is not allowed to be removed from the device.
-    return;
-  }
-  RemoveNonOwnerUserInternal(user_email, delegate);
-}
-
-void ChromeUserManager::SaveUserOAuthStatus(
-    const std::string& user_id,
-    user_manager::User::OAuthTokenStatus oauth_token_status) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  UserManagerBase::SaveUserOAuthStatus(user_id, oauth_token_status);
-
-  GetUserFlow(user_id)->HandleOAuthTokenStatusChange(oauth_token_status);
-}
-
-void ChromeUserManager::SaveUserDisplayName(
-    const std::string& user_id,
-    const base::string16& display_name) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  UserManagerBase::SaveUserDisplayName(user_id, display_name);
-
-  // Do not update local state if data stored or cached outside the user's
-  // cryptohome is to be treated as ephemeral.
-  if (!IsUserNonCryptohomeDataEphemeral(user_id))
-    supervised_user_manager_->UpdateManagerName(user_id, display_name);
-}
-
-void ChromeUserManager::StopPolicyObserverForTesting() {
-  avatar_policy_observer_.reset();
-  wallpaper_policy_observer_.reset();
-}
-
-void ChromeUserManager::Observe(int type,
-                                const content::NotificationSource& source,
-                                const content::NotificationDetails& details) {
-  switch (type) {
-    case chrome::NOTIFICATION_OWNERSHIP_STATUS_CHANGED:
-      if (!device_local_account_policy_service_) {
-        policy::BrowserPolicyConnectorChromeOS* connector =
-            g_browser_process->platform_part()
-                ->browser_policy_connector_chromeos();
-        device_local_account_policy_service_ =
-            connector->GetDeviceLocalAccountPolicyService();
-        if (device_local_account_policy_service_)
-          device_local_account_policy_service_->AddObserver(this);
-      }
-      RetrieveTrustedDevicePolicies();
-      UpdateOwnership();
-      break;
-    case chrome::NOTIFICATION_LOGIN_USER_PROFILE_PREPARED: {
-      Profile* profile = content::Details<Profile>(details).ptr();
-      if (IsUserLoggedIn() && !IsLoggedInAsGuest() && !IsLoggedInAsKioskApp()) {
-        if (IsLoggedInAsSupervisedUser())
-          SupervisedUserPasswordServiceFactory::GetForProfile(profile);
-        if (IsLoggedInAsRegularUser())
-          ManagerPasswordServiceFactory::GetForProfile(profile);
-
-        if (!profile->IsOffTheRecord()) {
-          AuthSyncObserver* sync_observer =
-              AuthSyncObserverFactory::GetInstance()->GetForProfile(profile);
-          sync_observer->StartObserving();
-          multi_profile_user_controller_->StartObserving(profile);
-        }
-      }
-      break;
-    }
-    case chrome::NOTIFICATION_PROFILE_CREATED: {
-      Profile* profile = content::Source<Profile>(source).ptr();
-      user_manager::User* user =
-          ProfileHelper::Get()->GetUserByProfile(profile);
-      if (user != NULL)
-        user->set_profile_is_created();
-
-      // If there is pending user switch, do it now.
-      if (!GetPendingUserSwitchID().empty()) {
-        // Call SwitchActiveUser async because otherwise it may cause
-        // ProfileManager::GetProfile before the profile gets registered
-        // in ProfileManager. It happens in case of sync profile load when
-        // NOTIFICATION_PROFILE_CREATED is called synchronously.
-        base::MessageLoop::current()->PostTask(
-            FROM_HERE,
-            base::Bind(&ChromeUserManager::SwitchActiveUser,
-                       weak_factory_.GetWeakPtr(),
-                       GetPendingUserSwitchID()));
-        SetPendingUserSwitchID(std::string());
-      }
-      break;
-    }
-    default:
-      NOTREACHED();
-  }
-}
-
-void ChromeUserManager::OnExternalDataSet(const std::string& policy,
-                                          const std::string& user_id) {
-  if (policy == policy::key::kUserAvatarImage)
-    GetUserImageManager(user_id)->OnExternalDataSet(policy);
-  else if (policy == policy::key::kWallpaperImage)
-    WallpaperManager::Get()->OnPolicySet(policy, user_id);
-  else
-    NOTREACHED();
-}
-
-void ChromeUserManager::OnExternalDataCleared(const std::string& policy,
-                                              const std::string& user_id) {
-  if (policy == policy::key::kUserAvatarImage)
-    GetUserImageManager(user_id)->OnExternalDataCleared(policy);
-  else if (policy == policy::key::kWallpaperImage)
-    WallpaperManager::Get()->OnPolicyCleared(policy, user_id);
-  else
-    NOTREACHED();
-}
-
-void ChromeUserManager::OnExternalDataFetched(const std::string& policy,
-                                              const std::string& user_id,
-                                              scoped_ptr<std::string> data) {
-  if (policy == policy::key::kUserAvatarImage)
-    GetUserImageManager(user_id)->OnExternalDataFetched(policy, data.Pass());
-  else if (policy == policy::key::kWallpaperImage)
-    WallpaperManager::Get()->OnPolicyFetched(policy, user_id, data.Pass());
-  else
-    NOTREACHED();
-}
-
-void ChromeUserManager::OnPolicyUpdated(const std::string& user_id) {
-  const user_manager::User* user = FindUser(user_id);
-  if (!user || user->GetType() != user_manager::USER_TYPE_PUBLIC_ACCOUNT)
-    return;
-  UpdatePublicAccountDisplayName(user_id);
-}
-
-void ChromeUserManager::OnDeviceLocalAccountsChanged() {
-  // No action needed here, changes to the list of device-local accounts get
-  // handled via the kAccountsPrefDeviceLocalAccounts device setting observer.
-}
-
-bool ChromeUserManager::CanCurrentUserLock() const {
-  return UserManagerBase::CanCurrentUserLock() &&
-         GetCurrentUserFlow()->CanLockScreen();
-}
-
-bool ChromeUserManager::IsUserNonCryptohomeDataEphemeral(
-    const std::string& user_id) const {
-  // Data belonging to the obsolete public accounts whose data has not been
-  // removed yet is not ephemeral.
-  bool is_obsolete_public_account = IsPublicAccountMarkedForRemoval(user_id);
-
-  return !is_obsolete_public_account &&
-         UserManagerBase::IsUserNonCryptohomeDataEphemeral(user_id);
-}
-
-bool ChromeUserManager::AreEphemeralUsersEnabled() const {
-  policy::BrowserPolicyConnectorChromeOS* connector =
-      g_browser_process->platform_part()->browser_policy_connector_chromeos();
-  return GetEphemeralUsersEnabled() &&
-         (connector->IsEnterpriseManaged() || !GetOwnerEmail().empty());
-}
-
-const std::string& ChromeUserManager::GetApplicationLocale() const {
-  return g_browser_process->GetApplicationLocale();
-}
-
-PrefService* ChromeUserManager::GetLocalState() const {
-  return g_browser_process ? g_browser_process->local_state() : NULL;
-}
-
-bool ChromeUserManager::IsEnterpriseManaged() const {
-  policy::BrowserPolicyConnectorChromeOS* connector =
-      g_browser_process->platform_part()->browser_policy_connector_chromeos();
-  return connector->IsEnterpriseManaged();
-}
-
-void ChromeUserManager::LoadPublicAccounts(
-    std::set<std::string>* public_sessions_set) {
-  const base::ListValue* prefs_public_sessions =
-      GetLocalState()->GetList(kPublicAccounts);
-  std::vector<std::string> public_sessions;
-  ParseUserList(*prefs_public_sessions,
-                std::set<std::string>(),
-                &public_sessions,
-                public_sessions_set);
-  for (std::vector<std::string>::const_iterator it = public_sessions.begin();
-       it != public_sessions.end();
-       ++it) {
-    users_.push_back(user_manager::User::CreatePublicAccountUser(*it));
-    UpdatePublicAccountDisplayName(*it);
-  }
-}
-
-void ChromeUserManager::PerformPreUserListLoadingActions() {
-  // Clean up user list first. All code down the path should be synchronous,
-  // so that local state after transaction rollback is in consistent state.
-  // This process also should not trigger EnsureUsersLoaded again.
-  if (supervised_user_manager_->HasFailedUserCreationTransaction())
-    supervised_user_manager_->RollbackUserCreationTransaction();
-}
-
-void ChromeUserManager::PerformPostUserListLoadingActions() {
-  for (user_manager::UserList::iterator ui = users_.begin(), ue = users_.end();
-       ui != ue;
-       ++ui) {
-    GetUserImageManager((*ui)->email())->LoadUserImage();
-  }
-}
-
-void ChromeUserManager::PerformPostUserLoggedInActions(bool browser_restart) {
-  // Initialize the session length limiter and start it only if
-  // session limit is defined by the policy.
-  session_length_limiter_.reset(
-      new SessionLengthLimiter(NULL, browser_restart));
-}
-
-bool ChromeUserManager::IsDemoApp(const std::string& user_id) const {
-  return DemoAppLauncher::IsDemoAppSession(user_id);
-}
-
-bool ChromeUserManager::IsKioskApp(const std::string& user_id) const {
-  policy::DeviceLocalAccount::Type device_local_account_type;
-  return policy::IsDeviceLocalAccountUser(user_id,
-                                          &device_local_account_type) &&
-         device_local_account_type ==
-             policy::DeviceLocalAccount::TYPE_KIOSK_APP;
-}
-
-bool ChromeUserManager::IsPublicAccountMarkedForRemoval(
-    const std::string& user_id) const {
-  return user_id ==
-         GetLocalState()->GetString(kPublicAccountPendingDataRemoval);
-}
-
-void ChromeUserManager::RetrieveTrustedDevicePolicies() {
-  // Local state may not be initialized in unit_tests.
-  if (!GetLocalState())
-    return;
-
-  SetEphemeralUsersEnabled(false);
-  SetOwnerEmail(std::string());
-
-  // Schedule a callback if device policy has not yet been verified.
-  if (CrosSettingsProvider::TRUSTED !=
-      cros_settings_->PrepareTrustedValues(
-          base::Bind(&ChromeUserManager::RetrieveTrustedDevicePolicies,
-                     weak_factory_.GetWeakPtr()))) {
-    return;
-  }
-
-  bool ephemeral_users_enabled = false;
-  cros_settings_->GetBoolean(kAccountsPrefEphemeralUsersEnabled,
-                             &ephemeral_users_enabled);
-  SetEphemeralUsersEnabled(ephemeral_users_enabled);
-
-  std::string owner_email;
-  cros_settings_->GetString(kDeviceOwner, &owner_email);
-  SetOwnerEmail(owner_email);
-
-  EnsureUsersLoaded();
-
-  bool changed = UpdateAndCleanUpPublicAccounts(
-      policy::GetDeviceLocalAccounts(cros_settings_));
-
-  // If ephemeral users are enabled and we are on the login screen, take this
-  // opportunity to clean up by removing all regular users except the owner.
-  if (GetEphemeralUsersEnabled() && !IsUserLoggedIn()) {
-    ListPrefUpdate prefs_users_update(GetLocalState(), kRegularUsers);
-    prefs_users_update->Clear();
-    for (user_manager::UserList::iterator it = users_.begin();
-         it != users_.end();) {
-      const std::string user_email = (*it)->email();
-      if ((*it)->GetType() == user_manager::USER_TYPE_REGULAR &&
-          user_email != GetOwnerEmail()) {
-        RemoveNonCryptohomeData(user_email);
-        DeleteUser(*it);
-        it = users_.erase(it);
-        changed = true;
-      } else {
-        if ((*it)->GetType() != user_manager::USER_TYPE_PUBLIC_ACCOUNT)
-          prefs_users_update->Append(new base::StringValue(user_email));
-        ++it;
-      }
-    }
-  }
-
-  if (changed)
-    NotifyUserListChanged();
-}
-
-void ChromeUserManager::GuestUserLoggedIn() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  UserManagerBase::GuestUserLoggedIn();
-
-  // TODO(nkostylev): Add support for passing guest session cryptohome
-  // mount point. Legacy (--login-profile) value will be used for now.
-  // http://crosbug.com/230859
-  active_user_->SetStubImage(
-      user_manager::UserImage(
-          *ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
-              IDR_PROFILE_PICTURE_LOADING)),
-      user_manager::User::USER_IMAGE_INVALID,
-      false);
-
-  // Initializes wallpaper after active_user_ is set.
-  WallpaperManager::Get()->SetUserWallpaperNow(chromeos::login::kGuestUserName);
-}
-
-void ChromeUserManager::RegularUserLoggedIn(const std::string& user_id) {
-  UserManagerBase::RegularUserLoggedIn(user_id);
-
-  if (IsCurrentUserNew())
-    WallpaperManager::Get()->SetUserWallpaperNow(user_id);
-
-  GetUserImageManager(user_id)->UserLoggedIn(IsCurrentUserNew(), false);
-
-  WallpaperManager::Get()->EnsureLoggedInUserWallpaperLoaded();
-
-  // Make sure that new data is persisted to Local State.
-  GetLocalState()->CommitPendingWrite();
-}
-
-void ChromeUserManager::RegularUserLoggedInAsEphemeral(
-    const std::string& user_id) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  UserManagerBase::RegularUserLoggedInAsEphemeral(user_id);
-
-  GetUserImageManager(user_id)->UserLoggedIn(IsCurrentUserNew(), false);
-  WallpaperManager::Get()->SetUserWallpaperNow(user_id);
-}
-
-void ChromeUserManager::SupervisedUserLoggedIn(const std::string& user_id) {
-  // TODO(nkostylev): Refactor, share code with RegularUserLoggedIn().
-
-  // Remove the user from the user list.
-  active_user_ = RemoveRegularOrSupervisedUserFromList(user_id);
-
-  // If the user was not found on the user list, create a new user.
-  if (!GetActiveUser()) {
-    SetIsCurrentUserNew(true);
-    active_user_ = user_manager::User::CreateSupervisedUser(user_id);
-    // Leaving OAuth token status at the default state = unknown.
-    WallpaperManager::Get()->SetUserWallpaperNow(user_id);
-  } else {
-    if (supervised_user_manager_->CheckForFirstRun(user_id)) {
-      SetIsCurrentUserNew(true);
-      WallpaperManager::Get()->SetUserWallpaperNow(user_id);
-    } else {
-      SetIsCurrentUserNew(false);
-    }
-  }
-
-  // Add the user to the front of the user list.
-  ListPrefUpdate prefs_users_update(GetLocalState(), kRegularUsers);
-  prefs_users_update->Insert(0, new base::StringValue(user_id));
-  users_.insert(users_.begin(), active_user_);
-
-  // Now that user is in the list, save display name.
-  if (IsCurrentUserNew()) {
-    SaveUserDisplayName(GetActiveUser()->email(),
-                        GetActiveUser()->GetDisplayName());
-  }
-
-  GetUserImageManager(user_id)->UserLoggedIn(IsCurrentUserNew(), true);
-  WallpaperManager::Get()->EnsureLoggedInUserWallpaperLoaded();
-
-  // Make sure that new data is persisted to Local State.
-  GetLocalState()->CommitPendingWrite();
-}
-
-void ChromeUserManager::PublicAccountUserLoggedIn(user_manager::User* user) {
-  SetIsCurrentUserNew(true);
-  active_user_ = user;
-
-  // The UserImageManager chooses a random avatar picture when a user logs in
-  // for the first time. Tell the UserImageManager that this user is not new to
-  // prevent the avatar from getting changed.
-  GetUserImageManager(user->email())->UserLoggedIn(false, true);
-  WallpaperManager::Get()->EnsureLoggedInUserWallpaperLoaded();
-}
-
-void ChromeUserManager::KioskAppLoggedIn(const std::string& app_id) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  policy::DeviceLocalAccount::Type device_local_account_type;
-  DCHECK(policy::IsDeviceLocalAccountUser(app_id, &device_local_account_type));
-  DCHECK_EQ(policy::DeviceLocalAccount::TYPE_KIOSK_APP,
-            device_local_account_type);
-
-  active_user_ = user_manager::User::CreateKioskAppUser(app_id);
-  active_user_->SetStubImage(
-      user_manager::UserImage(
-          *ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
-              IDR_PROFILE_PICTURE_LOADING)),
-      user_manager::User::USER_IMAGE_INVALID,
-      false);
-
-  WallpaperManager::Get()->SetUserWallpaperNow(app_id);
-
-  // TODO(bartfab): Add KioskAppUsers to the users_ list and keep metadata like
-  // the kiosk_app_id in these objects, removing the need to re-parse the
-  // device-local account list here to extract the kiosk_app_id.
-  const std::vector<policy::DeviceLocalAccount> device_local_accounts =
-      policy::GetDeviceLocalAccounts(cros_settings_);
-  const policy::DeviceLocalAccount* account = NULL;
-  for (std::vector<policy::DeviceLocalAccount>::const_iterator it =
-           device_local_accounts.begin();
-       it != device_local_accounts.end();
-       ++it) {
-    if (it->user_id == app_id) {
-      account = &*it;
-      break;
-    }
-  }
-  std::string kiosk_app_id;
-  if (account) {
-    kiosk_app_id = account->kiosk_app_id;
-  } else {
-    LOG(ERROR) << "Logged into nonexistent kiosk-app account: " << app_id;
-    NOTREACHED();
-  }
-
-  CommandLine* command_line = CommandLine::ForCurrentProcess();
-  command_line->AppendSwitch(::switches::kForceAppMode);
-  command_line->AppendSwitchASCII(::switches::kAppId, kiosk_app_id);
-
-  // Disable window animation since kiosk app runs in a single full screen
-  // window and window animation causes start-up janks.
-  command_line->AppendSwitch(wm::switches::kWindowAnimationsDisabled);
-}
-
-void ChromeUserManager::DemoAccountLoggedIn() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  active_user_ =
-      user_manager::User::CreateKioskAppUser(DemoAppLauncher::kDemoUserName);
-  active_user_->SetStubImage(
-      user_manager::UserImage(
-          *ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
-              IDR_PROFILE_PICTURE_LOADING)),
-      user_manager::User::USER_IMAGE_INVALID,
-      false);
-  WallpaperManager::Get()->SetUserWallpaperNow(DemoAppLauncher::kDemoUserName);
-
-  CommandLine* command_line = CommandLine::ForCurrentProcess();
-  command_line->AppendSwitch(::switches::kForceAppMode);
-  command_line->AppendSwitchASCII(::switches::kAppId,
-                                  DemoAppLauncher::kDemoAppId);
-
-  // Disable window animation since the demo app runs in a single full screen
-  // window and window animation causes start-up janks.
-  CommandLine::ForCurrentProcess()->AppendSwitch(
-      wm::switches::kWindowAnimationsDisabled);
-}
-
-void ChromeUserManager::RetailModeUserLoggedIn() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  SetIsCurrentUserNew(true);
-  active_user_ = user_manager::User::CreateRetailModeUser();
-  GetUserImageManager(chromeos::login::kRetailModeUserName)
-      ->UserLoggedIn(IsCurrentUserNew(), true);
-  WallpaperManager::Get()->SetUserWallpaperNow(
-      chromeos::login::kRetailModeUserName);
-}
-
-void ChromeUserManager::NotifyOnLogin() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-  UserSessionManager::OverrideHomedir();
-  UpdateNumberOfUsers();
-
-  UserManagerBase::NotifyOnLogin();
-
-  // TODO(nkostylev): Deprecate this notification in favor of
-  // ActiveUserChanged() observer call.
-  content::NotificationService::current()->Notify(
-      chrome::NOTIFICATION_LOGIN_USER_CHANGED,
-      content::Source<UserManager>(this),
-      content::Details<const user_manager::User>(GetActiveUser()));
-
-  UserSessionManager::GetInstance()->PerformPostUserLoggedInActions();
-}
-
-void ChromeUserManager::UpdateOwnership() {
-  bool is_owner = DeviceSettingsService::Get()->HasPrivateOwnerKey();
-  VLOG(1) << "Current user " << (is_owner ? "is owner" : "is not owner");
-
-  SetCurrentUserIsOwner(is_owner);
-}
-
-void ChromeUserManager::RemoveNonCryptohomeData(const std::string& user_id) {
-  UserManagerBase::RemoveNonCryptohomeData(user_id);
-
-  WallpaperManager::Get()->RemoveUserWallpaperInfo(user_id);
-  GetUserImageManager(user_id)->DeleteUserImage();
-
-  supervised_user_manager_->RemoveNonCryptohomeData(user_id);
-
-  multi_profile_user_controller_->RemoveCachedValues(user_id);
-}
-
-void ChromeUserManager::CleanUpPublicAccountNonCryptohomeDataPendingRemoval() {
-  PrefService* local_state = GetLocalState();
-  const std::string public_account_pending_data_removal =
-      local_state->GetString(kPublicAccountPendingDataRemoval);
-  if (public_account_pending_data_removal.empty() ||
-      (IsUserLoggedIn() &&
-       public_account_pending_data_removal == GetActiveUser()->email())) {
-    return;
-  }
-
-  RemoveNonCryptohomeData(public_account_pending_data_removal);
-  local_state->ClearPref(kPublicAccountPendingDataRemoval);
-}
-
-void ChromeUserManager::CleanUpPublicAccountNonCryptohomeData(
-    const std::vector<std::string>& old_public_accounts) {
-  std::set<std::string> users;
-  for (user_manager::UserList::const_iterator it = users_.begin();
-       it != users_.end();
-       ++it)
-    users.insert((*it)->email());
-
-  // If the user is logged into a public account that has been removed from the
-  // user list, mark the account's data as pending removal after logout.
-  if (IsLoggedInAsPublicAccount()) {
-    const std::string active_user_id = GetActiveUser()->email();
-    if (users.find(active_user_id) == users.end()) {
-      GetLocalState()->SetString(kPublicAccountPendingDataRemoval,
-                                 active_user_id);
-      users.insert(active_user_id);
-    }
-  }
-
-  // Remove the data belonging to any other public accounts that are no longer
-  // found on the user list.
-  for (std::vector<std::string>::const_iterator it =
-           old_public_accounts.begin();
-       it != old_public_accounts.end();
-       ++it) {
-    if (users.find(*it) == users.end())
-      RemoveNonCryptohomeData(*it);
-  }
-}
-
-bool ChromeUserManager::UpdateAndCleanUpPublicAccounts(
-    const std::vector<policy::DeviceLocalAccount>& device_local_accounts) {
-  // Try to remove any public account data marked as pending removal.
-  CleanUpPublicAccountNonCryptohomeDataPendingRemoval();
-
-  // Get the current list of public accounts.
-  std::vector<std::string> old_public_accounts;
-  for (user_manager::UserList::const_iterator it = users_.begin();
-       it != users_.end();
-       ++it) {
-    if ((*it)->GetType() == user_manager::USER_TYPE_PUBLIC_ACCOUNT)
-      old_public_accounts.push_back((*it)->email());
-  }
-
-  // Get the new list of public accounts from policy.
-  std::vector<std::string> new_public_accounts;
-  for (std::vector<policy::DeviceLocalAccount>::const_iterator it =
-           device_local_accounts.begin();
-       it != device_local_accounts.end();
-       ++it) {
-    // TODO(mnissler, nkostylev, bartfab): Process Kiosk Apps within the
-    // standard login framework: http://crbug.com/234694
-    if (it->type == policy::DeviceLocalAccount::TYPE_PUBLIC_SESSION)
-      new_public_accounts.push_back(it->user_id);
-  }
-
-  // If the list of public accounts has not changed, return.
-  if (new_public_accounts.size() == old_public_accounts.size()) {
-    bool changed = false;
-    for (size_t i = 0; i < new_public_accounts.size(); ++i) {
-      if (new_public_accounts[i] != old_public_accounts[i]) {
-        changed = true;
-        break;
-      }
-    }
-    if (!changed)
-      return false;
-  }
-
-  // Persist the new list of public accounts in a pref.
-  ListPrefUpdate prefs_public_accounts_update(GetLocalState(), kPublicAccounts);
-  prefs_public_accounts_update->Clear();
-  for (std::vector<std::string>::const_iterator it =
-           new_public_accounts.begin();
-       it != new_public_accounts.end();
-       ++it) {
-    prefs_public_accounts_update->AppendString(*it);
-  }
-
-  // Remove the old public accounts from the user list.
-  for (user_manager::UserList::iterator it = users_.begin();
-       it != users_.end();) {
-    if ((*it)->GetType() == user_manager::USER_TYPE_PUBLIC_ACCOUNT) {
-      if (*it != GetLoggedInUser())
-        DeleteUser(*it);
-      it = users_.erase(it);
-    } else {
-      ++it;
-    }
-  }
-
-  // Add the new public accounts to the front of the user list.
-  for (std::vector<std::string>::const_reverse_iterator it =
-           new_public_accounts.rbegin();
-       it != new_public_accounts.rend();
-       ++it) {
-    if (IsLoggedInAsPublicAccount() && *it == GetActiveUser()->email())
-      users_.insert(users_.begin(), GetLoggedInUser());
-    else
-      users_.insert(users_.begin(),
-                    user_manager::User::CreatePublicAccountUser(*it));
-    UpdatePublicAccountDisplayName(*it);
-  }
-
-  for (user_manager::UserList::iterator
-           ui = users_.begin(),
-           ue = users_.begin() + new_public_accounts.size();
-       ui != ue;
-       ++ui) {
-    GetUserImageManager((*ui)->email())->LoadUserImage();
-  }
-
-  // Remove data belonging to public accounts that are no longer found on the
-  // user list.
-  CleanUpPublicAccountNonCryptohomeData(old_public_accounts);
-
-  return true;
-}
-
-void ChromeUserManager::UpdatePublicAccountDisplayName(
-    const std::string& user_id) {
-  std::string display_name;
-
-  if (device_local_account_policy_service_) {
-    policy::DeviceLocalAccountPolicyBroker* broker =
-        device_local_account_policy_service_->GetBrokerForUser(user_id);
-    if (broker)
-      display_name = broker->GetDisplayName();
-  }
-
-  // Set or clear the display name.
-  SaveUserDisplayName(user_id, base::UTF8ToUTF16(display_name));
-}
-
-UserFlow* ChromeUserManager::GetCurrentUserFlow() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  if (!IsUserLoggedIn())
-    return GetDefaultUserFlow();
-  return GetUserFlow(GetLoggedInUser()->email());
-}
-
-UserFlow* ChromeUserManager::GetUserFlow(const std::string& user_id) const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  FlowMap::const_iterator it = specific_flows_.find(user_id);
-  if (it != specific_flows_.end())
-    return it->second;
-  return GetDefaultUserFlow();
-}
-
-void ChromeUserManager::SetUserFlow(const std::string& user_id,
-                                    UserFlow* flow) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  ResetUserFlow(user_id);
-  specific_flows_[user_id] = flow;
-}
-
-void ChromeUserManager::ResetUserFlow(const std::string& user_id) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  FlowMap::iterator it = specific_flows_.find(user_id);
-  if (it != specific_flows_.end()) {
-    delete it->second;
-    specific_flows_.erase(it);
-  }
-}
-
-bool ChromeUserManager::AreSupervisedUsersAllowed() const {
-  bool supervised_users_allowed = false;
-  cros_settings_->GetBoolean(kAccountsPrefSupervisedUsersEnabled,
-                             &supervised_users_allowed);
-  return supervised_users_allowed;
-}
-
-UserFlow* ChromeUserManager::GetDefaultUserFlow() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  if (!default_flow_.get())
-    default_flow_.reset(new DefaultUserFlow());
-  return default_flow_.get();
-}
-
-void ChromeUserManager::NotifyUserListChanged() {
-  content::NotificationService::current()->Notify(
-      chrome::NOTIFICATION_USER_LIST_CHANGED,
-      content::Source<UserManager>(this),
-      content::NotificationService::NoDetails());
-}
-
-void ChromeUserManager::NotifyUserAddedToSession(
-    const user_manager::User* added_user,
-    bool user_switch_pending) {
-  if (user_switch_pending)
-    SetPendingUserSwitchID(added_user->email());
-
-  UpdateNumberOfUsers();
-  UserManagerBase::NotifyUserAddedToSession(added_user, user_switch_pending);
-}
-
-void ChromeUserManager::OnUserNotAllowed(const std::string& user_email) {
-  LOG(ERROR) << "Shutdown session because a user is not allowed to be in the "
-                "current session";
-  chromeos::ShowMultiprofilesSessionAbortedDialog(user_email);
-}
-
-void ChromeUserManager::UpdateNumberOfUsers() {
-  size_t users = GetLoggedInUsers().size();
-  if (users) {
-    // Write the user number as UMA stat when a multi user session is possible.
-    if ((users + GetUsersAdmittedForMultiProfile().size()) > 1)
-      ash::MultiProfileUMA::RecordUserCount(users);
-  }
-
-  base::debug::SetCrashKeyValue(
-      crash_keys::kNumberOfUsers,
-      base::StringPrintf("%" PRIuS, GetLoggedInUsers().size()));
+// static
+ChromeUserManager* ChromeUserManager::Get() {
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
+  return user_manager ? static_cast<ChromeUserManager*>(user_manager) : NULL;
 }
 
 }  // namespace chromeos
diff --git a/chrome/browser/chromeos/login/users/chrome_user_manager.h b/chrome/browser/chromeos/login/users/chrome_user_manager.h
index 84dd7d9..c6a74eb 100644
--- a/chrome/browser/chromeos/login/users/chrome_user_manager.h
+++ b/chrome/browser/chromeos/login/users/chrome_user_manager.h
@@ -5,222 +5,53 @@
 #ifndef CHROME_BROWSER_CHROMEOS_LOGIN_USERS_CHROME_USER_MANAGER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_CHROME_USER_MANAGER_H_
 
-#include <map>
-#include <string>
-#include <vector>
-
 #include "base/basictypes.h"
-#include "base/containers/hash_tables.h"
-#include "base/memory/linked_ptr.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/memory/weak_ptr.h"
-#include "base/observer_list.h"
-#include "base/synchronization/lock.h"
-#include "base/time/time.h"
-#include "chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.h"
-#include "chrome/browser/chromeos/login/users/multi_profile_user_controller_delegate.h"
-#include "chrome/browser/chromeos/login/users/user_manager_base.h"
-#include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
-#include "chrome/browser/chromeos/policy/cloud_external_data_policy_observer.h"
-#include "chrome/browser/chromeos/policy/device_local_account_policy_service.h"
-#include "chrome/browser/chromeos/settings/cros_settings.h"
-#include "chrome/browser/chromeos/settings/device_settings_service.h"
-#include "components/user_manager/user.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
-
-class PrefService;
-class ProfileSyncService;
+#include "components/user_manager/user_manager_base.h"
 
-namespace policy {
-struct DeviceLocalAccount;
+namespace base {
+class TaskRunner;
 }
 
 namespace chromeos {
 
 class MultiProfileUserController;
-class RemoveUserDelegate;
-class SupervisedUserManagerImpl;
-class SessionLengthLimiter;
+class SupervisedUserManager;
+class UserFlow;
+class UserImageManager;
 
-// Chrome specific implementation of the UserManager.
-class ChromeUserManager
-    : public UserManagerBase,
-      public content::NotificationObserver,
-      public policy::CloudExternalDataPolicyObserver::Delegate,
-      public policy::DeviceLocalAccountPolicyService::Observer,
-      public MultiProfileUserControllerDelegate {
+// Chrome specific interface of the UserManager.
+class ChromeUserManager : public user_manager::UserManagerBase {
  public:
+  ChromeUserManager(scoped_refptr<base::TaskRunner> task_runner,
+                    scoped_refptr<base::TaskRunner> blocking_task_runner);
   virtual ~ChromeUserManager();
 
-  // UserManager implementation:
-  virtual void Shutdown() OVERRIDE;
-  virtual MultiProfileUserController* GetMultiProfileUserController() OVERRIDE;
-  virtual UserImageManager* GetUserImageManager(
-      const std::string& user_id) OVERRIDE;
-  virtual SupervisedUserManager* GetSupervisedUserManager() OVERRIDE;
-  virtual user_manager::UserList GetUsersAdmittedForMultiProfile()
-      const OVERRIDE;
-  virtual user_manager::UserList GetUnlockUsers() const OVERRIDE;
-  virtual void SessionStarted() OVERRIDE;
-  virtual void SaveUserOAuthStatus(
-      const std::string& user_id,
-      user_manager::User::OAuthTokenStatus oauth_token_status) OVERRIDE;
-  virtual void SaveUserDisplayName(const std::string& user_id,
-                                   const base::string16& display_name) OVERRIDE;
-  virtual bool CanCurrentUserLock() const OVERRIDE;
-  virtual bool IsUserNonCryptohomeDataEphemeral(
-      const std::string& user_id) const OVERRIDE;
-
-  virtual UserFlow* GetCurrentUserFlow() const OVERRIDE;
-  virtual UserFlow* GetUserFlow(const std::string& user_id) const OVERRIDE;
-  virtual void SetUserFlow(const std::string& user_id, UserFlow* flow) OVERRIDE;
-  virtual void ResetUserFlow(const std::string& user_id) OVERRIDE;
-  virtual bool AreSupervisedUsersAllowed() const OVERRIDE;
-
-  // content::NotificationObserver implementation.
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
-
-  // policy::CloudExternalDataPolicyObserver::Delegate:
-  virtual void OnExternalDataSet(const std::string& policy,
-                                 const std::string& user_id) OVERRIDE;
-  virtual void OnExternalDataCleared(const std::string& policy,
-                                     const std::string& user_id) OVERRIDE;
-  virtual void OnExternalDataFetched(const std::string& policy,
-                                     const std::string& user_id,
-                                     scoped_ptr<std::string> data) OVERRIDE;
-
-  // policy::DeviceLocalAccountPolicyService::Observer implementation.
-  virtual void OnPolicyUpdated(const std::string& user_id) OVERRIDE;
-  virtual void OnDeviceLocalAccountsChanged() OVERRIDE;
-
-  void StopPolicyObserverForTesting();
-
- protected:
-  // UserManagerBase implementation:
-  virtual bool AreEphemeralUsersEnabled() const OVERRIDE;
-  virtual const std::string& GetApplicationLocale() const OVERRIDE;
-  virtual PrefService* GetLocalState() const OVERRIDE;
-  virtual bool IsEnterpriseManaged() const OVERRIDE;
-  virtual void LoadPublicAccounts(std::set<std::string>* users_set) OVERRIDE;
-  virtual void NotifyOnLogin() OVERRIDE;
-  virtual void NotifyUserAddedToSession(const user_manager::User* added_user,
-                                        bool user_switch_pending) OVERRIDE;
-  virtual void PerformPreUserListLoadingActions() OVERRIDE;
-  virtual void PerformPostUserListLoadingActions() OVERRIDE;
-  virtual void PerformPostUserLoggedInActions(bool browser_restart) OVERRIDE;
-  virtual void RemoveNonCryptohomeData(const std::string& user_id) OVERRIDE;
-  virtual void RemoveUserInternal(const std::string& user_email,
-                                  RemoveUserDelegate* delegate) OVERRIDE;
-  virtual bool IsDemoApp(const std::string& user_id) const OVERRIDE;
-  virtual bool IsKioskApp(const std::string& user_id) const OVERRIDE;
-  virtual bool IsPublicAccountMarkedForRemoval(
-      const std::string& user_id) const OVERRIDE;
-  virtual void DemoAccountLoggedIn() OVERRIDE;
-  virtual void GuestUserLoggedIn() OVERRIDE;
-  virtual void KioskAppLoggedIn(const std::string& app_id) OVERRIDE;
-  virtual void PublicAccountUserLoggedIn(user_manager::User* user) OVERRIDE;
-  virtual void RegularUserLoggedIn(const std::string& user_id) OVERRIDE;
-  virtual void RegularUserLoggedInAsEphemeral(
-      const std::string& user_id) OVERRIDE;
-  virtual void RetailModeUserLoggedIn() OVERRIDE;
-  virtual void SupervisedUserLoggedIn(const std::string& user_id) OVERRIDE;
-
- private:
-  friend class SupervisedUserManagerImpl;
-  friend class UserManager;
-  friend class UserManagerTest;
-  friend class WallpaperManager;
-  friend class WallpaperManagerTest;
-
-  typedef base::hash_map<std::string, linked_ptr<UserImageManager> >
-      UserImageManagerMap;
-
-  ChromeUserManager();
-
-  // Retrieves trusted device policies and removes users from the persistent
-  // list if ephemeral users are enabled. Schedules a callback to itself if
-  // trusted device policies are not yet available.
-  void RetrieveTrustedDevicePolicies();
-
-  // Updates current user ownership on UI thread.
-  void UpdateOwnership();
-
-  // If data for a public account is marked as pending removal and the user is
-  // no longer logged into that account, removes the data.
-  void CleanUpPublicAccountNonCryptohomeDataPendingRemoval();
-
-  // Removes data belonging to public accounts that are no longer found on the
-  // user list. If the user is currently logged into one of these accounts, the
-  // data for that account is not removed immediately but marked as pending
-  // removal after logout.
-  void CleanUpPublicAccountNonCryptohomeData(
-      const std::vector<std::string>& old_public_accounts);
-
-  // Replaces the list of public accounts with those found in
-  // |device_local_accounts|. Ensures that data belonging to accounts no longer
-  // on the list is removed. Returns |true| if the list has changed.
-  // Public accounts are defined by policy. This method is called whenever an
-  // updated list of public accounts is received from policy.
-  bool UpdateAndCleanUpPublicAccounts(
-      const std::vector<policy::DeviceLocalAccount>& device_local_accounts);
-
-  // Updates the display name for public account |username| from policy settings
-  // associated with that username.
-  void UpdatePublicAccountDisplayName(const std::string& user_id);
-
-  // Notifies the UI about a change to the user list.
-  void NotifyUserListChanged();
-
-  // Lazily creates default user flow.
-  UserFlow* GetDefaultUserFlow() const;
-
-  // MultiProfileUserControllerDelegate implementation:
-  virtual void OnUserNotAllowed(const std::string& user_email) OVERRIDE;
-
-  // Update the number of users.
-  void UpdateNumberOfUsers();
-
-  // Interface to the signed settings store.
-  CrosSettings* cros_settings_;
-
-  // Interface to device-local account definitions and associated policy.
-  policy::DeviceLocalAccountPolicyService* device_local_account_policy_service_;
-
-  content::NotificationRegistrar registrar_;
-
-  // User avatar managers.
-  UserImageManagerMap user_image_managers_;
-
-  // Supervised user manager.
-  scoped_ptr<SupervisedUserManagerImpl> supervised_user_manager_;
-
-  // Session length limiter.
-  scoped_ptr<SessionLengthLimiter> session_length_limiter_;
-
-  typedef std::map<std::string, UserFlow*> FlowMap;
-
-  // Lazy-initialized default flow.
-  mutable scoped_ptr<UserFlow> default_flow_;
-
-  // Specific flows by user e-mail. Keys should be canonicalized before
-  // access.
-  FlowMap specific_flows_;
+  // Returns current ChromeUserManager or NULL if instance hasn't been
+  // yet initialized.
+  static ChromeUserManager* Get();
 
-  scoped_ptr<CrosSettings::ObserverSubscription> local_accounts_subscription_;
+  virtual MultiProfileUserController* GetMultiProfileUserController() = 0;
+  virtual UserImageManager* GetUserImageManager(const std::string& user_id) = 0;
+  virtual SupervisedUserManager* GetSupervisedUserManager() = 0;
 
-  scoped_ptr<MultiProfileUserController> multi_profile_user_controller_;
+  // Method that allows to set |flow| for user identified by |user_id|.
+  // Flow should be set before login attempt.
+  // Takes ownership of the |flow|, |flow| will be deleted in case of login
+  // failure.
+  virtual void SetUserFlow(const std::string& user_id, UserFlow* flow) = 0;
 
-  // Observer for the policy that can be used to manage user images.
-  scoped_ptr<policy::CloudExternalDataPolicyObserver> avatar_policy_observer_;
+  // Return user flow for current user. Returns instance of DefaultUserFlow if
+  // no flow was defined for current user, or user is not logged in.
+  // Returned value should not be cached.
+  virtual UserFlow* GetCurrentUserFlow() const = 0;
 
-  // Observer for the policy that can be used to manage wallpapers.
-  scoped_ptr<policy::CloudExternalDataPolicyObserver>
-      wallpaper_policy_observer_;
+  // Return user flow for user identified by |user_id|. Returns instance of
+  // DefaultUserFlow if no flow was defined for user.
+  // Returned value should not be cached.
+  virtual UserFlow* GetUserFlow(const std::string& user_id) const = 0;
 
-  base::WeakPtrFactory<ChromeUserManager> weak_factory_;
+  // Resets user flow for user identified by |user_id|.
+  virtual void ResetUserFlow(const std::string& user_id) = 0;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeUserManager);
 };
diff --git a/chrome/browser/chromeos/login/users/chrome_user_manager_impl.cc b/chrome/browser/chromeos/login/users/chrome_user_manager_impl.cc
new file mode 100644
index 0000000..32aab49
--- /dev/null
+++ b/chrome/browser/chromeos/login/users/chrome_user_manager_impl.cc
@@ -0,0 +1,1040 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/chromeos/login/users/chrome_user_manager_impl.h"
+
+#include <cstddef>
+#include <set>
+
+#include "ash/multi_profile_uma.h"
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/command_line.h"
+#include "base/compiler_specific.h"
+#include "base/format_macros.h"
+#include "base/logging.h"
+#include "base/metrics/histogram.h"
+#include "base/prefs/pref_registry_simple.h"
+#include "base/prefs/pref_service.h"
+#include "base/prefs/scoped_user_pref_update.h"
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
+#include "base/strings/utf_string_conversions.h"
+#include "base/thread_task_runner_handle.h"
+#include "base/values.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/chrome_notification_types.h"
+#include "chrome/browser/chromeos/login/demo_mode/demo_app_launcher.h"
+#include "chrome/browser/chromeos/login/session/user_session_manager.h"
+#include "chrome/browser/chromeos/login/signin/auth_sync_observer.h"
+#include "chrome/browser/chromeos/login/signin/auth_sync_observer_factory.h"
+#include "chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.h"
+#include "chrome/browser/chromeos/login/users/multi_profile_user_controller.h"
+#include "chrome/browser/chromeos/login/users/supervised_user_manager_impl.h"
+#include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
+#include "chrome/browser/chromeos/policy/device_local_account.h"
+#include "chrome/browser/chromeos/profiles/multiprofiles_session_aborted_dialog.h"
+#include "chrome/browser/chromeos/profiles/profile_helper.h"
+#include "chrome/browser/chromeos/session_length_limiter.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/supervised_user/chromeos/manager_password_service_factory.h"
+#include "chrome/browser/supervised_user/chromeos/supervised_user_password_service_factory.h"
+#include "chrome/common/chrome_constants.h"
+#include "chrome/common/chrome_switches.h"
+#include "chrome/common/crash_keys.h"
+#include "chrome/common/pref_names.h"
+#include "chrome/grit/theme_resources.h"
+#include "chromeos/chromeos_switches.h"
+#include "chromeos/login/user_names.h"
+#include "chromeos/settings/cros_settings_names.h"
+#include "components/session_manager/core/session_manager.h"
+#include "components/user_manager/remove_user_delegate.h"
+#include "components/user_manager/user_image/user_image.h"
+#include "components/user_manager/user_type.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/notification_service.h"
+#include "policy/policy_constants.h"
+#include "ui/base/resource/resource_bundle.h"
+#include "ui/wm/core/wm_core_switches.h"
+
+using content::BrowserThread;
+
+namespace chromeos {
+namespace {
+
+// A vector pref of the the regular users known on this device, arranged in LRU
+// order.
+const char kRegularUsers[] = "LoggedInUsers";
+
+// A vector pref of the public accounts defined on this device.
+const char kPublicAccounts[] = "PublicAccounts";
+
+// A string pref that gets set when a public account is removed but a user is
+// currently logged into that account, requiring the account's data to be
+// removed after logout.
+const char kPublicAccountPendingDataRemoval[] =
+    "PublicAccountPendingDataRemoval";
+
+}  // namespace
+
+// static
+void ChromeUserManagerImpl::RegisterPrefs(PrefRegistrySimple* registry) {
+  ChromeUserManager::RegisterPrefs(registry);
+
+  registry->RegisterListPref(kPublicAccounts);
+  registry->RegisterStringPref(kPublicAccountPendingDataRemoval, std::string());
+  SupervisedUserManager::RegisterPrefs(registry);
+  SessionLengthLimiter::RegisterPrefs(registry);
+}
+
+// static
+scoped_ptr<ChromeUserManager> ChromeUserManagerImpl::CreateChromeUserManager() {
+  return scoped_ptr<ChromeUserManager>(new ChromeUserManagerImpl());
+}
+
+ChromeUserManagerImpl::ChromeUserManagerImpl()
+    : ChromeUserManager(base::ThreadTaskRunnerHandle::Get(),
+                        BrowserThread::GetBlockingPool()),
+      cros_settings_(CrosSettings::Get()),
+      device_local_account_policy_service_(NULL),
+      supervised_user_manager_(new SupervisedUserManagerImpl(this)),
+      weak_factory_(this) {
+  UpdateNumberOfUsers();
+
+  // UserManager instance should be used only on UI thread.
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  registrar_.Add(this,
+                 chrome::NOTIFICATION_OWNERSHIP_STATUS_CHANGED,
+                 content::NotificationService::AllSources());
+  registrar_.Add(this,
+                 chrome::NOTIFICATION_LOGIN_USER_PROFILE_PREPARED,
+                 content::NotificationService::AllSources());
+  registrar_.Add(this,
+                 chrome::NOTIFICATION_PROFILE_CREATED,
+                 content::NotificationService::AllSources());
+
+  // Since we're in ctor postpone any actions till this is fully created.
+  if (base::MessageLoop::current()) {
+    base::MessageLoop::current()->PostTask(
+        FROM_HERE,
+        base::Bind(&ChromeUserManagerImpl::RetrieveTrustedDevicePolicies,
+                   weak_factory_.GetWeakPtr()));
+  }
+
+  local_accounts_subscription_ = cros_settings_->AddSettingsObserver(
+      kAccountsPrefDeviceLocalAccounts,
+      base::Bind(&ChromeUserManagerImpl::RetrieveTrustedDevicePolicies,
+                 weak_factory_.GetWeakPtr()));
+  multi_profile_user_controller_.reset(
+      new MultiProfileUserController(this, GetLocalState()));
+
+  policy::BrowserPolicyConnectorChromeOS* connector =
+      g_browser_process->platform_part()->browser_policy_connector_chromeos();
+  avatar_policy_observer_.reset(new policy::CloudExternalDataPolicyObserver(
+      cros_settings_,
+      connector->GetDeviceLocalAccountPolicyService(),
+      policy::key::kUserAvatarImage,
+      this));
+  avatar_policy_observer_->Init();
+
+  wallpaper_policy_observer_.reset(new policy::CloudExternalDataPolicyObserver(
+      cros_settings_,
+      connector->GetDeviceLocalAccountPolicyService(),
+      policy::key::kWallpaperImage,
+      this));
+  wallpaper_policy_observer_->Init();
+}
+
+ChromeUserManagerImpl::~ChromeUserManagerImpl() {
+}
+
+void ChromeUserManagerImpl::Shutdown() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  ChromeUserManager::Shutdown();
+
+  local_accounts_subscription_.reset();
+
+  // Stop the session length limiter.
+  session_length_limiter_.reset();
+
+  if (device_local_account_policy_service_)
+    device_local_account_policy_service_->RemoveObserver(this);
+
+  for (UserImageManagerMap::iterator it = user_image_managers_.begin(),
+                                     ie = user_image_managers_.end();
+       it != ie;
+       ++it) {
+    it->second->Shutdown();
+  }
+  multi_profile_user_controller_.reset();
+  avatar_policy_observer_.reset();
+  wallpaper_policy_observer_.reset();
+  registrar_.RemoveAll();
+}
+
+MultiProfileUserController*
+ChromeUserManagerImpl::GetMultiProfileUserController() {
+  return multi_profile_user_controller_.get();
+}
+
+UserImageManager* ChromeUserManagerImpl::GetUserImageManager(
+    const std::string& user_id) {
+  UserImageManagerMap::iterator ui = user_image_managers_.find(user_id);
+  if (ui != user_image_managers_.end())
+    return ui->second.get();
+  linked_ptr<UserImageManagerImpl> mgr(new UserImageManagerImpl(user_id, this));
+  user_image_managers_[user_id] = mgr;
+  return mgr.get();
+}
+
+SupervisedUserManager* ChromeUserManagerImpl::GetSupervisedUserManager() {
+  return supervised_user_manager_.get();
+}
+
+user_manager::UserList ChromeUserManagerImpl::GetUsersAdmittedForMultiProfile()
+    const {
+  // Supervised users are not allowed to use multi-profiles.
+  if (GetLoggedInUsers().size() == 1 &&
+      GetPrimaryUser()->GetType() != user_manager::USER_TYPE_REGULAR) {
+    return user_manager::UserList();
+  }
+
+  user_manager::UserList result;
+  const user_manager::UserList& users = GetUsers();
+  for (user_manager::UserList::const_iterator it = users.begin();
+       it != users.end();
+       ++it) {
+    if ((*it)->GetType() == user_manager::USER_TYPE_REGULAR &&
+        !(*it)->is_logged_in()) {
+      MultiProfileUserController::UserAllowedInSessionReason check;
+      multi_profile_user_controller_->IsUserAllowedInSession((*it)->email(),
+                                                             &check);
+      if (check ==
+          MultiProfileUserController::NOT_ALLOWED_PRIMARY_USER_POLICY_FORBIDS) {
+        return user_manager::UserList();
+      }
+
+      // Users with a policy that prevents them being added to a session will be
+      // shown in login UI but will be grayed out.
+      // Same applies to owner account (see http://crbug.com/385034).
+      if (check == MultiProfileUserController::ALLOWED ||
+          check == MultiProfileUserController::NOT_ALLOWED_POLICY_FORBIDS ||
+          check == MultiProfileUserController::NOT_ALLOWED_OWNER_AS_SECONDARY ||
+          check ==
+              MultiProfileUserController::NOT_ALLOWED_POLICY_CERT_TAINTED) {
+        result.push_back(*it);
+      }
+    }
+  }
+
+  return result;
+}
+
+user_manager::UserList ChromeUserManagerImpl::GetUnlockUsers() const {
+  const user_manager::UserList& logged_in_users = GetLoggedInUsers();
+  if (logged_in_users.empty())
+    return user_manager::UserList();
+
+  user_manager::UserList unlock_users;
+  Profile* profile =
+      ProfileHelper::Get()->GetProfileByUserUnsafe(GetPrimaryUser());
+  std::string primary_behavior =
+      profile->GetPrefs()->GetString(prefs::kMultiProfileUserBehavior);
+
+  // Specific case: only one logged in user or
+  // primary user has primary-only multi-profile policy.
+  if (logged_in_users.size() == 1 ||
+      primary_behavior == MultiProfileUserController::kBehaviorPrimaryOnly) {
+    if (GetPrimaryUser()->can_lock())
+      unlock_users.push_back(primary_user_);
+  } else {
+    // Fill list of potential unlock users based on multi-profile policy state.
+    for (user_manager::UserList::const_iterator it = logged_in_users.begin();
+         it != logged_in_users.end();
+         ++it) {
+      user_manager::User* user = (*it);
+      Profile* profile = ProfileHelper::Get()->GetProfileByUserUnsafe(user);
+      const std::string behavior =
+          profile->GetPrefs()->GetString(prefs::kMultiProfileUserBehavior);
+      if (behavior == MultiProfileUserController::kBehaviorUnrestricted &&
+          user->can_lock()) {
+        unlock_users.push_back(user);
+      } else if (behavior == MultiProfileUserController::kBehaviorPrimaryOnly) {
+        NOTREACHED()
+            << "Spotted primary-only multi-profile policy for non-primary user";
+      }
+    }
+  }
+
+  return unlock_users;
+}
+
+void ChromeUserManagerImpl::SessionStarted() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  ChromeUserManager::SessionStarted();
+
+  content::NotificationService::current()->Notify(
+      chrome::NOTIFICATION_SESSION_STARTED,
+      content::Source<UserManager>(this),
+      content::Details<const user_manager::User>(GetActiveUser()));
+}
+
+void ChromeUserManagerImpl::RemoveUserInternal(
+    const std::string& user_email,
+    user_manager::RemoveUserDelegate* delegate) {
+  CrosSettings* cros_settings = CrosSettings::Get();
+
+  const base::Closure& callback =
+      base::Bind(&ChromeUserManagerImpl::RemoveUserInternal,
+                 weak_factory_.GetWeakPtr(),
+                 user_email,
+                 delegate);
+
+  // Ensure the value of owner email has been fetched.
+  if (CrosSettingsProvider::TRUSTED !=
+      cros_settings->PrepareTrustedValues(callback)) {
+    // Value of owner email is not fetched yet.  RemoveUserInternal will be
+    // called again after fetch completion.
+    return;
+  }
+  std::string owner;
+  cros_settings->GetString(kDeviceOwner, &owner);
+  if (user_email == owner) {
+    // Owner is not allowed to be removed from the device.
+    return;
+  }
+  RemoveNonOwnerUserInternal(user_email, delegate);
+}
+
+void ChromeUserManagerImpl::SaveUserOAuthStatus(
+    const std::string& user_id,
+    user_manager::User::OAuthTokenStatus oauth_token_status) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  ChromeUserManager::SaveUserOAuthStatus(user_id, oauth_token_status);
+
+  GetUserFlow(user_id)->HandleOAuthTokenStatusChange(oauth_token_status);
+}
+
+void ChromeUserManagerImpl::SaveUserDisplayName(
+    const std::string& user_id,
+    const base::string16& display_name) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  ChromeUserManager::SaveUserDisplayName(user_id, display_name);
+
+  // Do not update local state if data stored or cached outside the user's
+  // cryptohome is to be treated as ephemeral.
+  if (!IsUserNonCryptohomeDataEphemeral(user_id))
+    supervised_user_manager_->UpdateManagerName(user_id, display_name);
+}
+
+void ChromeUserManagerImpl::StopPolicyObserverForTesting() {
+  avatar_policy_observer_.reset();
+  wallpaper_policy_observer_.reset();
+}
+
+void ChromeUserManagerImpl::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  switch (type) {
+    case chrome::NOTIFICATION_OWNERSHIP_STATUS_CHANGED:
+      if (!device_local_account_policy_service_) {
+        policy::BrowserPolicyConnectorChromeOS* connector =
+            g_browser_process->platform_part()
+                ->browser_policy_connector_chromeos();
+        device_local_account_policy_service_ =
+            connector->GetDeviceLocalAccountPolicyService();
+        if (device_local_account_policy_service_)
+          device_local_account_policy_service_->AddObserver(this);
+      }
+      RetrieveTrustedDevicePolicies();
+      UpdateOwnership();
+      break;
+    case chrome::NOTIFICATION_LOGIN_USER_PROFILE_PREPARED: {
+      Profile* profile = content::Details<Profile>(details).ptr();
+      if (IsUserLoggedIn() && !IsLoggedInAsGuest() && !IsLoggedInAsKioskApp()) {
+        if (IsLoggedInAsSupervisedUser())
+          SupervisedUserPasswordServiceFactory::GetForProfile(profile);
+        if (IsLoggedInAsRegularUser())
+          ManagerPasswordServiceFactory::GetForProfile(profile);
+
+        if (!profile->IsOffTheRecord()) {
+          AuthSyncObserver* sync_observer =
+              AuthSyncObserverFactory::GetInstance()->GetForProfile(profile);
+          sync_observer->StartObserving();
+          multi_profile_user_controller_->StartObserving(profile);
+        }
+      }
+      break;
+    }
+    case chrome::NOTIFICATION_PROFILE_CREATED: {
+      Profile* profile = content::Source<Profile>(source).ptr();
+      user_manager::User* user =
+          ProfileHelper::Get()->GetUserByProfile(profile);
+      if (user != NULL)
+        user->set_profile_is_created();
+
+      // If there is pending user switch, do it now.
+      if (!GetPendingUserSwitchID().empty()) {
+        // Call SwitchActiveUser async because otherwise it may cause
+        // ProfileManager::GetProfile before the profile gets registered
+        // in ProfileManager. It happens in case of sync profile load when
+        // NOTIFICATION_PROFILE_CREATED is called synchronously.
+        base::MessageLoop::current()->PostTask(
+            FROM_HERE,
+            base::Bind(&ChromeUserManagerImpl::SwitchActiveUser,
+                       weak_factory_.GetWeakPtr(),
+                       GetPendingUserSwitchID()));
+        SetPendingUserSwitchID(std::string());
+      }
+      break;
+    }
+    default:
+      NOTREACHED();
+  }
+}
+
+void ChromeUserManagerImpl::OnExternalDataSet(const std::string& policy,
+                                              const std::string& user_id) {
+  if (policy == policy::key::kUserAvatarImage)
+    GetUserImageManager(user_id)->OnExternalDataSet(policy);
+  else if (policy == policy::key::kWallpaperImage)
+    WallpaperManager::Get()->OnPolicySet(policy, user_id);
+  else
+    NOTREACHED();
+}
+
+void ChromeUserManagerImpl::OnExternalDataCleared(const std::string& policy,
+                                                  const std::string& user_id) {
+  if (policy == policy::key::kUserAvatarImage)
+    GetUserImageManager(user_id)->OnExternalDataCleared(policy);
+  else if (policy == policy::key::kWallpaperImage)
+    WallpaperManager::Get()->OnPolicyCleared(policy, user_id);
+  else
+    NOTREACHED();
+}
+
+void ChromeUserManagerImpl::OnExternalDataFetched(
+    const std::string& policy,
+    const std::string& user_id,
+    scoped_ptr<std::string> data) {
+  if (policy == policy::key::kUserAvatarImage)
+    GetUserImageManager(user_id)->OnExternalDataFetched(policy, data.Pass());
+  else if (policy == policy::key::kWallpaperImage)
+    WallpaperManager::Get()->OnPolicyFetched(policy, user_id, data.Pass());
+  else
+    NOTREACHED();
+}
+
+void ChromeUserManagerImpl::OnPolicyUpdated(const std::string& user_id) {
+  const user_manager::User* user = FindUser(user_id);
+  if (!user || user->GetType() != user_manager::USER_TYPE_PUBLIC_ACCOUNT)
+    return;
+  UpdatePublicAccountDisplayName(user_id);
+}
+
+void ChromeUserManagerImpl::OnDeviceLocalAccountsChanged() {
+  // No action needed here, changes to the list of device-local accounts get
+  // handled via the kAccountsPrefDeviceLocalAccounts device setting observer.
+}
+
+bool ChromeUserManagerImpl::CanCurrentUserLock() const {
+  return ChromeUserManager::CanCurrentUserLock() &&
+         GetCurrentUserFlow()->CanLockScreen();
+}
+
+bool ChromeUserManagerImpl::IsUserNonCryptohomeDataEphemeral(
+    const std::string& user_id) const {
+  // Data belonging to the obsolete public accounts whose data has not been
+  // removed yet is not ephemeral.
+  bool is_obsolete_public_account = IsPublicAccountMarkedForRemoval(user_id);
+
+  return !is_obsolete_public_account &&
+         ChromeUserManager::IsUserNonCryptohomeDataEphemeral(user_id);
+}
+
+bool ChromeUserManagerImpl::AreEphemeralUsersEnabled() const {
+  policy::BrowserPolicyConnectorChromeOS* connector =
+      g_browser_process->platform_part()->browser_policy_connector_chromeos();
+  return GetEphemeralUsersEnabled() &&
+         (connector->IsEnterpriseManaged() || !GetOwnerEmail().empty());
+}
+
+const std::string& ChromeUserManagerImpl::GetApplicationLocale() const {
+  return g_browser_process->GetApplicationLocale();
+}
+
+PrefService* ChromeUserManagerImpl::GetLocalState() const {
+  return g_browser_process ? g_browser_process->local_state() : NULL;
+}
+
+void ChromeUserManagerImpl::HandleUserOAuthTokenStatusChange(
+    const std::string& user_id,
+    user_manager::User::OAuthTokenStatus status) const {
+  GetUserFlow(user_id)->HandleOAuthTokenStatusChange(status);
+}
+
+bool ChromeUserManagerImpl::IsEnterpriseManaged() const {
+  policy::BrowserPolicyConnectorChromeOS* connector =
+      g_browser_process->platform_part()->browser_policy_connector_chromeos();
+  return connector->IsEnterpriseManaged();
+}
+
+void ChromeUserManagerImpl::LoadPublicAccounts(
+    std::set<std::string>* public_sessions_set) {
+  const base::ListValue* prefs_public_sessions =
+      GetLocalState()->GetList(kPublicAccounts);
+  std::vector<std::string> public_sessions;
+  ParseUserList(*prefs_public_sessions,
+                std::set<std::string>(),
+                &public_sessions,
+                public_sessions_set);
+  for (std::vector<std::string>::const_iterator it = public_sessions.begin();
+       it != public_sessions.end();
+       ++it) {
+    users_.push_back(user_manager::User::CreatePublicAccountUser(*it));
+    UpdatePublicAccountDisplayName(*it);
+  }
+}
+
+void ChromeUserManagerImpl::PerformPreUserListLoadingActions() {
+  // Clean up user list first. All code down the path should be synchronous,
+  // so that local state after transaction rollback is in consistent state.
+  // This process also should not trigger EnsureUsersLoaded again.
+  if (supervised_user_manager_->HasFailedUserCreationTransaction())
+    supervised_user_manager_->RollbackUserCreationTransaction();
+}
+
+void ChromeUserManagerImpl::PerformPostUserListLoadingActions() {
+  for (user_manager::UserList::iterator ui = users_.begin(), ue = users_.end();
+       ui != ue;
+       ++ui) {
+    GetUserImageManager((*ui)->email())->LoadUserImage();
+  }
+}
+
+void ChromeUserManagerImpl::PerformPostUserLoggedInActions(
+    bool browser_restart) {
+  // Initialize the session length limiter and start it only if
+  // session limit is defined by the policy.
+  session_length_limiter_.reset(
+      new SessionLengthLimiter(NULL, browser_restart));
+}
+
+bool ChromeUserManagerImpl::IsDemoApp(const std::string& user_id) const {
+  return DemoAppLauncher::IsDemoAppSession(user_id);
+}
+
+bool ChromeUserManagerImpl::IsKioskApp(const std::string& user_id) const {
+  policy::DeviceLocalAccount::Type device_local_account_type;
+  return policy::IsDeviceLocalAccountUser(user_id,
+                                          &device_local_account_type) &&
+         device_local_account_type ==
+             policy::DeviceLocalAccount::TYPE_KIOSK_APP;
+}
+
+bool ChromeUserManagerImpl::IsPublicAccountMarkedForRemoval(
+    const std::string& user_id) const {
+  return user_id ==
+         GetLocalState()->GetString(kPublicAccountPendingDataRemoval);
+}
+
+void ChromeUserManagerImpl::RetrieveTrustedDevicePolicies() {
+  // Local state may not be initialized in unit_tests.
+  if (!GetLocalState())
+    return;
+
+  SetEphemeralUsersEnabled(false);
+  SetOwnerEmail(std::string());
+
+  // Schedule a callback if device policy has not yet been verified.
+  if (CrosSettingsProvider::TRUSTED !=
+      cros_settings_->PrepareTrustedValues(
+          base::Bind(&ChromeUserManagerImpl::RetrieveTrustedDevicePolicies,
+                     weak_factory_.GetWeakPtr()))) {
+    return;
+  }
+
+  bool ephemeral_users_enabled = false;
+  cros_settings_->GetBoolean(kAccountsPrefEphemeralUsersEnabled,
+                             &ephemeral_users_enabled);
+  SetEphemeralUsersEnabled(ephemeral_users_enabled);
+
+  std::string owner_email;
+  cros_settings_->GetString(kDeviceOwner, &owner_email);
+  SetOwnerEmail(owner_email);
+
+  EnsureUsersLoaded();
+
+  bool changed = UpdateAndCleanUpPublicAccounts(
+      policy::GetDeviceLocalAccounts(cros_settings_));
+
+  // If ephemeral users are enabled and we are on the login screen, take this
+  // opportunity to clean up by removing all regular users except the owner.
+  if (GetEphemeralUsersEnabled() && !IsUserLoggedIn()) {
+    ListPrefUpdate prefs_users_update(GetLocalState(), kRegularUsers);
+    prefs_users_update->Clear();
+    for (user_manager::UserList::iterator it = users_.begin();
+         it != users_.end();) {
+      const std::string user_email = (*it)->email();
+      if ((*it)->GetType() == user_manager::USER_TYPE_REGULAR &&
+          user_email != GetOwnerEmail()) {
+        RemoveNonCryptohomeData(user_email);
+        DeleteUser(*it);
+        it = users_.erase(it);
+        changed = true;
+      } else {
+        if ((*it)->GetType() != user_manager::USER_TYPE_PUBLIC_ACCOUNT)
+          prefs_users_update->Append(new base::StringValue(user_email));
+        ++it;
+      }
+    }
+  }
+
+  if (changed)
+    NotifyUserListChanged();
+}
+
+void ChromeUserManagerImpl::GuestUserLoggedIn() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  ChromeUserManager::GuestUserLoggedIn();
+
+  // TODO(nkostylev): Add support for passing guest session cryptohome
+  // mount point. Legacy (--login-profile) value will be used for now.
+  // http://crosbug.com/230859
+  active_user_->SetStubImage(
+      user_manager::UserImage(
+          *ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
+              IDR_PROFILE_PICTURE_LOADING)),
+      user_manager::User::USER_IMAGE_INVALID,
+      false);
+
+  // Initializes wallpaper after active_user_ is set.
+  WallpaperManager::Get()->SetUserWallpaperNow(chromeos::login::kGuestUserName);
+}
+
+void ChromeUserManagerImpl::RegularUserLoggedIn(const std::string& user_id) {
+  ChromeUserManager::RegularUserLoggedIn(user_id);
+
+  if (IsCurrentUserNew())
+    WallpaperManager::Get()->SetUserWallpaperNow(user_id);
+
+  GetUserImageManager(user_id)->UserLoggedIn(IsCurrentUserNew(), false);
+
+  WallpaperManager::Get()->EnsureLoggedInUserWallpaperLoaded();
+
+  // Make sure that new data is persisted to Local State.
+  GetLocalState()->CommitPendingWrite();
+}
+
+void ChromeUserManagerImpl::RegularUserLoggedInAsEphemeral(
+    const std::string& user_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  ChromeUserManager::RegularUserLoggedInAsEphemeral(user_id);
+
+  GetUserImageManager(user_id)->UserLoggedIn(IsCurrentUserNew(), false);
+  WallpaperManager::Get()->SetUserWallpaperNow(user_id);
+}
+
+void ChromeUserManagerImpl::SupervisedUserLoggedIn(const std::string& user_id) {
+  // TODO(nkostylev): Refactor, share code with RegularUserLoggedIn().
+
+  // Remove the user from the user list.
+  active_user_ = RemoveRegularOrSupervisedUserFromList(user_id);
+
+  // If the user was not found on the user list, create a new user.
+  if (!GetActiveUser()) {
+    SetIsCurrentUserNew(true);
+    active_user_ = user_manager::User::CreateSupervisedUser(user_id);
+    // Leaving OAuth token status at the default state = unknown.
+    WallpaperManager::Get()->SetUserWallpaperNow(user_id);
+  } else {
+    if (supervised_user_manager_->CheckForFirstRun(user_id)) {
+      SetIsCurrentUserNew(true);
+      WallpaperManager::Get()->SetUserWallpaperNow(user_id);
+    } else {
+      SetIsCurrentUserNew(false);
+    }
+  }
+
+  // Add the user to the front of the user list.
+  ListPrefUpdate prefs_users_update(GetLocalState(), kRegularUsers);
+  prefs_users_update->Insert(0, new base::StringValue(user_id));
+  users_.insert(users_.begin(), active_user_);
+
+  // Now that user is in the list, save display name.
+  if (IsCurrentUserNew()) {
+    SaveUserDisplayName(GetActiveUser()->email(),
+                        GetActiveUser()->GetDisplayName());
+  }
+
+  GetUserImageManager(user_id)->UserLoggedIn(IsCurrentUserNew(), true);
+  WallpaperManager::Get()->EnsureLoggedInUserWallpaperLoaded();
+
+  // Make sure that new data is persisted to Local State.
+  GetLocalState()->CommitPendingWrite();
+}
+
+void ChromeUserManagerImpl::PublicAccountUserLoggedIn(
+    user_manager::User* user) {
+  SetIsCurrentUserNew(true);
+  active_user_ = user;
+
+  // The UserImageManager chooses a random avatar picture when a user logs in
+  // for the first time. Tell the UserImageManager that this user is not new to
+  // prevent the avatar from getting changed.
+  GetUserImageManager(user->email())->UserLoggedIn(false, true);
+  WallpaperManager::Get()->EnsureLoggedInUserWallpaperLoaded();
+}
+
+void ChromeUserManagerImpl::KioskAppLoggedIn(const std::string& app_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  policy::DeviceLocalAccount::Type device_local_account_type;
+  DCHECK(policy::IsDeviceLocalAccountUser(app_id, &device_local_account_type));
+  DCHECK_EQ(policy::DeviceLocalAccount::TYPE_KIOSK_APP,
+            device_local_account_type);
+
+  active_user_ = user_manager::User::CreateKioskAppUser(app_id);
+  active_user_->SetStubImage(
+      user_manager::UserImage(
+          *ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
+              IDR_PROFILE_PICTURE_LOADING)),
+      user_manager::User::USER_IMAGE_INVALID,
+      false);
+
+  WallpaperManager::Get()->SetUserWallpaperNow(app_id);
+
+  // TODO(bartfab): Add KioskAppUsers to the users_ list and keep metadata like
+  // the kiosk_app_id in these objects, removing the need to re-parse the
+  // device-local account list here to extract the kiosk_app_id.
+  const std::vector<policy::DeviceLocalAccount> device_local_accounts =
+      policy::GetDeviceLocalAccounts(cros_settings_);
+  const policy::DeviceLocalAccount* account = NULL;
+  for (std::vector<policy::DeviceLocalAccount>::const_iterator it =
+           device_local_accounts.begin();
+       it != device_local_accounts.end();
+       ++it) {
+    if (it->user_id == app_id) {
+      account = &*it;
+      break;
+    }
+  }
+  std::string kiosk_app_id;
+  if (account) {
+    kiosk_app_id = account->kiosk_app_id;
+  } else {
+    LOG(ERROR) << "Logged into nonexistent kiosk-app account: " << app_id;
+    NOTREACHED();
+  }
+
+  CommandLine* command_line = CommandLine::ForCurrentProcess();
+  command_line->AppendSwitch(::switches::kForceAppMode);
+  command_line->AppendSwitchASCII(::switches::kAppId, kiosk_app_id);
+
+  // Disable window animation since kiosk app runs in a single full screen
+  // window and window animation causes start-up janks.
+  command_line->AppendSwitch(wm::switches::kWindowAnimationsDisabled);
+}
+
+void ChromeUserManagerImpl::DemoAccountLoggedIn() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  active_user_ =
+      user_manager::User::CreateKioskAppUser(DemoAppLauncher::kDemoUserName);
+  active_user_->SetStubImage(
+      user_manager::UserImage(
+          *ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
+              IDR_PROFILE_PICTURE_LOADING)),
+      user_manager::User::USER_IMAGE_INVALID,
+      false);
+  WallpaperManager::Get()->SetUserWallpaperNow(DemoAppLauncher::kDemoUserName);
+
+  CommandLine* command_line = CommandLine::ForCurrentProcess();
+  command_line->AppendSwitch(::switches::kForceAppMode);
+  command_line->AppendSwitchASCII(::switches::kAppId,
+                                  DemoAppLauncher::kDemoAppId);
+
+  // Disable window animation since the demo app runs in a single full screen
+  // window and window animation causes start-up janks.
+  CommandLine::ForCurrentProcess()->AppendSwitch(
+      wm::switches::kWindowAnimationsDisabled);
+}
+
+void ChromeUserManagerImpl::RetailModeUserLoggedIn() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  SetIsCurrentUserNew(true);
+  active_user_ = user_manager::User::CreateRetailModeUser();
+  GetUserImageManager(chromeos::login::kRetailModeUserName)
+      ->UserLoggedIn(IsCurrentUserNew(), true);
+  WallpaperManager::Get()->SetUserWallpaperNow(
+      chromeos::login::kRetailModeUserName);
+}
+
+void ChromeUserManagerImpl::NotifyOnLogin() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  UserSessionManager::OverrideHomedir();
+  UpdateNumberOfUsers();
+
+  ChromeUserManager::NotifyOnLogin();
+
+  // TODO(nkostylev): Deprecate this notification in favor of
+  // ActiveUserChanged() observer call.
+  content::NotificationService::current()->Notify(
+      chrome::NOTIFICATION_LOGIN_USER_CHANGED,
+      content::Source<UserManager>(this),
+      content::Details<const user_manager::User>(GetActiveUser()));
+
+  UserSessionManager::GetInstance()->PerformPostUserLoggedInActions();
+}
+
+void ChromeUserManagerImpl::UpdateOwnership() {
+  bool is_owner = DeviceSettingsService::Get()->HasPrivateOwnerKey();
+  VLOG(1) << "Current user " << (is_owner ? "is owner" : "is not owner");
+
+  SetCurrentUserIsOwner(is_owner);
+}
+
+void ChromeUserManagerImpl::RemoveNonCryptohomeData(
+    const std::string& user_id) {
+  ChromeUserManager::RemoveNonCryptohomeData(user_id);
+
+  WallpaperManager::Get()->RemoveUserWallpaperInfo(user_id);
+  GetUserImageManager(user_id)->DeleteUserImage();
+
+  supervised_user_manager_->RemoveNonCryptohomeData(user_id);
+
+  multi_profile_user_controller_->RemoveCachedValues(user_id);
+}
+
+void
+ChromeUserManagerImpl::CleanUpPublicAccountNonCryptohomeDataPendingRemoval() {
+  PrefService* local_state = GetLocalState();
+  const std::string public_account_pending_data_removal =
+      local_state->GetString(kPublicAccountPendingDataRemoval);
+  if (public_account_pending_data_removal.empty() ||
+      (IsUserLoggedIn() &&
+       public_account_pending_data_removal == GetActiveUser()->email())) {
+    return;
+  }
+
+  RemoveNonCryptohomeData(public_account_pending_data_removal);
+  local_state->ClearPref(kPublicAccountPendingDataRemoval);
+}
+
+void ChromeUserManagerImpl::CleanUpPublicAccountNonCryptohomeData(
+    const std::vector<std::string>& old_public_accounts) {
+  std::set<std::string> users;
+  for (user_manager::UserList::const_iterator it = users_.begin();
+       it != users_.end();
+       ++it)
+    users.insert((*it)->email());
+
+  // If the user is logged into a public account that has been removed from the
+  // user list, mark the account's data as pending removal after logout.
+  if (IsLoggedInAsPublicAccount()) {
+    const std::string active_user_id = GetActiveUser()->email();
+    if (users.find(active_user_id) == users.end()) {
+      GetLocalState()->SetString(kPublicAccountPendingDataRemoval,
+                                 active_user_id);
+      users.insert(active_user_id);
+    }
+  }
+
+  // Remove the data belonging to any other public accounts that are no longer
+  // found on the user list.
+  for (std::vector<std::string>::const_iterator it =
+           old_public_accounts.begin();
+       it != old_public_accounts.end();
+       ++it) {
+    if (users.find(*it) == users.end())
+      RemoveNonCryptohomeData(*it);
+  }
+}
+
+bool ChromeUserManagerImpl::UpdateAndCleanUpPublicAccounts(
+    const std::vector<policy::DeviceLocalAccount>& device_local_accounts) {
+  // Try to remove any public account data marked as pending removal.
+  CleanUpPublicAccountNonCryptohomeDataPendingRemoval();
+
+  // Get the current list of public accounts.
+  std::vector<std::string> old_public_accounts;
+  for (user_manager::UserList::const_iterator it = users_.begin();
+       it != users_.end();
+       ++it) {
+    if ((*it)->GetType() == user_manager::USER_TYPE_PUBLIC_ACCOUNT)
+      old_public_accounts.push_back((*it)->email());
+  }
+
+  // Get the new list of public accounts from policy.
+  std::vector<std::string> new_public_accounts;
+  for (std::vector<policy::DeviceLocalAccount>::const_iterator it =
+           device_local_accounts.begin();
+       it != device_local_accounts.end();
+       ++it) {
+    // TODO(mnissler, nkostylev, bartfab): Process Kiosk Apps within the
+    // standard login framework: http://crbug.com/234694
+    if (it->type == policy::DeviceLocalAccount::TYPE_PUBLIC_SESSION)
+      new_public_accounts.push_back(it->user_id);
+  }
+
+  // If the list of public accounts has not changed, return.
+  if (new_public_accounts.size() == old_public_accounts.size()) {
+    bool changed = false;
+    for (size_t i = 0; i < new_public_accounts.size(); ++i) {
+      if (new_public_accounts[i] != old_public_accounts[i]) {
+        changed = true;
+        break;
+      }
+    }
+    if (!changed)
+      return false;
+  }
+
+  // Persist the new list of public accounts in a pref.
+  ListPrefUpdate prefs_public_accounts_update(GetLocalState(), kPublicAccounts);
+  prefs_public_accounts_update->Clear();
+  for (std::vector<std::string>::const_iterator it =
+           new_public_accounts.begin();
+       it != new_public_accounts.end();
+       ++it) {
+    prefs_public_accounts_update->AppendString(*it);
+  }
+
+  // Remove the old public accounts from the user list.
+  for (user_manager::UserList::iterator it = users_.begin();
+       it != users_.end();) {
+    if ((*it)->GetType() == user_manager::USER_TYPE_PUBLIC_ACCOUNT) {
+      if (*it != GetLoggedInUser())
+        DeleteUser(*it);
+      it = users_.erase(it);
+    } else {
+      ++it;
+    }
+  }
+
+  // Add the new public accounts to the front of the user list.
+  for (std::vector<std::string>::const_reverse_iterator it =
+           new_public_accounts.rbegin();
+       it != new_public_accounts.rend();
+       ++it) {
+    if (IsLoggedInAsPublicAccount() && *it == GetActiveUser()->email())
+      users_.insert(users_.begin(), GetLoggedInUser());
+    else
+      users_.insert(users_.begin(),
+                    user_manager::User::CreatePublicAccountUser(*it));
+    UpdatePublicAccountDisplayName(*it);
+  }
+
+  for (user_manager::UserList::iterator
+           ui = users_.begin(),
+           ue = users_.begin() + new_public_accounts.size();
+       ui != ue;
+       ++ui) {
+    GetUserImageManager((*ui)->email())->LoadUserImage();
+  }
+
+  // Remove data belonging to public accounts that are no longer found on the
+  // user list.
+  CleanUpPublicAccountNonCryptohomeData(old_public_accounts);
+
+  return true;
+}
+
+void ChromeUserManagerImpl::UpdatePublicAccountDisplayName(
+    const std::string& user_id) {
+  std::string display_name;
+
+  if (device_local_account_policy_service_) {
+    policy::DeviceLocalAccountPolicyBroker* broker =
+        device_local_account_policy_service_->GetBrokerForUser(user_id);
+    if (broker)
+      display_name = broker->GetDisplayName();
+  }
+
+  // Set or clear the display name.
+  SaveUserDisplayName(user_id, base::UTF8ToUTF16(display_name));
+}
+
+UserFlow* ChromeUserManagerImpl::GetCurrentUserFlow() const {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (!IsUserLoggedIn())
+    return GetDefaultUserFlow();
+  return GetUserFlow(GetLoggedInUser()->email());
+}
+
+UserFlow* ChromeUserManagerImpl::GetUserFlow(const std::string& user_id) const {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  FlowMap::const_iterator it = specific_flows_.find(user_id);
+  if (it != specific_flows_.end())
+    return it->second;
+  return GetDefaultUserFlow();
+}
+
+void ChromeUserManagerImpl::SetUserFlow(const std::string& user_id,
+                                        UserFlow* flow) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  ResetUserFlow(user_id);
+  specific_flows_[user_id] = flow;
+}
+
+void ChromeUserManagerImpl::ResetUserFlow(const std::string& user_id) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  FlowMap::iterator it = specific_flows_.find(user_id);
+  if (it != specific_flows_.end()) {
+    delete it->second;
+    specific_flows_.erase(it);
+  }
+}
+
+bool ChromeUserManagerImpl::AreSupervisedUsersAllowed() const {
+  bool supervised_users_allowed = false;
+  cros_settings_->GetBoolean(kAccountsPrefSupervisedUsersEnabled,
+                             &supervised_users_allowed);
+  return supervised_users_allowed;
+}
+
+UserFlow* ChromeUserManagerImpl::GetDefaultUserFlow() const {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (!default_flow_.get())
+    default_flow_.reset(new DefaultUserFlow());
+  return default_flow_.get();
+}
+
+void ChromeUserManagerImpl::NotifyUserListChanged() {
+  content::NotificationService::current()->Notify(
+      chrome::NOTIFICATION_USER_LIST_CHANGED,
+      content::Source<UserManager>(this),
+      content::NotificationService::NoDetails());
+}
+
+void ChromeUserManagerImpl::NotifyUserAddedToSession(
+    const user_manager::User* added_user,
+    bool user_switch_pending) {
+  if (user_switch_pending)
+    SetPendingUserSwitchID(added_user->email());
+
+  UpdateNumberOfUsers();
+  ChromeUserManager::NotifyUserAddedToSession(added_user, user_switch_pending);
+}
+
+void ChromeUserManagerImpl::OnUserNotAllowed(const std::string& user_email) {
+  LOG(ERROR) << "Shutdown session because a user is not allowed to be in the "
+                "current session";
+  chromeos::ShowMultiprofilesSessionAbortedDialog(user_email);
+}
+
+void ChromeUserManagerImpl::UpdateNumberOfUsers() {
+  size_t users = GetLoggedInUsers().size();
+  if (users) {
+    // Write the user number as UMA stat when a multi user session is possible.
+    if ((users + GetUsersAdmittedForMultiProfile().size()) > 1)
+      ash::MultiProfileUMA::RecordUserCount(users);
+  }
+
+  base::debug::SetCrashKeyValue(
+      crash_keys::kNumberOfUsers,
+      base::StringPrintf("%" PRIuS, GetLoggedInUsers().size()));
+}
+
+}  // namespace chromeos
diff --git a/chrome/browser/chromeos/login/users/chrome_user_manager_impl.h b/chrome/browser/chromeos/login/users/chrome_user_manager_impl.h
new file mode 100644
index 0000000..9ba3c20
--- /dev/null
+++ b/chrome/browser/chromeos/login/users/chrome_user_manager_impl.h
@@ -0,0 +1,245 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_CHROMEOS_LOGIN_USERS_CHROME_USER_MANAGER_IMPL_H_
+#define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_CHROME_USER_MANAGER_IMPL_H_
+
+#include <map>
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/containers/hash_tables.h"
+#include "base/memory/linked_ptr.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "base/observer_list.h"
+#include "base/synchronization/lock.h"
+#include "base/time/time.h"
+#include "chrome/browser/chromeos/login/user_flow.h"
+#include "chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
+#include "chrome/browser/chromeos/login/users/multi_profile_user_controller_delegate.h"
+#include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
+#include "chrome/browser/chromeos/policy/cloud_external_data_policy_observer.h"
+#include "chrome/browser/chromeos/policy/device_local_account_policy_service.h"
+#include "chrome/browser/chromeos/settings/cros_settings.h"
+#include "chrome/browser/chromeos/settings/device_settings_service.h"
+#include "components/user_manager/user.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
+
+class PrefRegistrySimple;
+class PrefService;
+class ProfileSyncService;
+
+namespace policy {
+struct DeviceLocalAccount;
+}
+
+namespace user_manager {
+class RemoveUserDelegate;
+}
+
+namespace chromeos {
+
+class MultiProfileUserController;
+class SupervisedUserManagerImpl;
+class SessionLengthLimiter;
+
+// Chrome specific implementation of the UserManager.
+class ChromeUserManagerImpl
+    : public ChromeUserManager,
+      public content::NotificationObserver,
+      public policy::CloudExternalDataPolicyObserver::Delegate,
+      public policy::DeviceLocalAccountPolicyService::Observer,
+      public MultiProfileUserControllerDelegate {
+ public:
+  virtual ~ChromeUserManagerImpl();
+
+  // Creates ChromeUserManagerImpl instance.
+  static scoped_ptr<ChromeUserManager> CreateChromeUserManager();
+
+  // Registers user manager preferences.
+  static void RegisterPrefs(PrefRegistrySimple* registry);
+
+  // ChromeUserManager implementation:
+  virtual MultiProfileUserController* GetMultiProfileUserController() OVERRIDE;
+  virtual UserImageManager* GetUserImageManager(
+      const std::string& user_id) OVERRIDE;
+  virtual SupervisedUserManager* GetSupervisedUserManager() OVERRIDE;
+  virtual UserFlow* GetCurrentUserFlow() const OVERRIDE;
+  virtual UserFlow* GetUserFlow(const std::string& user_id) const OVERRIDE;
+  virtual void SetUserFlow(const std::string& user_id, UserFlow* flow) OVERRIDE;
+  virtual void ResetUserFlow(const std::string& user_id) OVERRIDE;
+
+  // UserManager implementation:
+  virtual void Shutdown() OVERRIDE;
+  virtual user_manager::UserList GetUsersAdmittedForMultiProfile()
+      const OVERRIDE;
+  virtual user_manager::UserList GetUnlockUsers() const OVERRIDE;
+  virtual void SessionStarted() OVERRIDE;
+  virtual void SaveUserOAuthStatus(
+      const std::string& user_id,
+      user_manager::User::OAuthTokenStatus oauth_token_status) OVERRIDE;
+  virtual void SaveUserDisplayName(const std::string& user_id,
+                                   const base::string16& display_name) OVERRIDE;
+  virtual bool CanCurrentUserLock() const OVERRIDE;
+  virtual bool IsUserNonCryptohomeDataEphemeral(
+      const std::string& user_id) const OVERRIDE;
+  virtual bool AreSupervisedUsersAllowed() const OVERRIDE;
+
+  // content::NotificationObserver implementation.
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+  // policy::CloudExternalDataPolicyObserver::Delegate:
+  virtual void OnExternalDataSet(const std::string& policy,
+                                 const std::string& user_id) OVERRIDE;
+  virtual void OnExternalDataCleared(const std::string& policy,
+                                     const std::string& user_id) OVERRIDE;
+  virtual void OnExternalDataFetched(const std::string& policy,
+                                     const std::string& user_id,
+                                     scoped_ptr<std::string> data) OVERRIDE;
+
+  // policy::DeviceLocalAccountPolicyService::Observer implementation.
+  virtual void OnPolicyUpdated(const std::string& user_id) OVERRIDE;
+  virtual void OnDeviceLocalAccountsChanged() OVERRIDE;
+
+  void StopPolicyObserverForTesting();
+
+ protected:
+  // UserManagerBase implementation:
+  virtual bool AreEphemeralUsersEnabled() const OVERRIDE;
+  virtual const std::string& GetApplicationLocale() const OVERRIDE;
+  virtual PrefService* GetLocalState() const OVERRIDE;
+  virtual void HandleUserOAuthTokenStatusChange(
+      const std::string& user_id,
+      user_manager::User::OAuthTokenStatus status) const OVERRIDE;
+  virtual bool IsEnterpriseManaged() const OVERRIDE;
+  virtual void LoadPublicAccounts(std::set<std::string>* users_set) OVERRIDE;
+  virtual void NotifyOnLogin() OVERRIDE;
+  virtual void NotifyUserAddedToSession(const user_manager::User* added_user,
+                                        bool user_switch_pending) OVERRIDE;
+  virtual void PerformPreUserListLoadingActions() OVERRIDE;
+  virtual void PerformPostUserListLoadingActions() OVERRIDE;
+  virtual void PerformPostUserLoggedInActions(bool browser_restart) OVERRIDE;
+  virtual void RemoveNonCryptohomeData(const std::string& user_id) OVERRIDE;
+  virtual void RemoveUserInternal(
+      const std::string& user_email,
+      user_manager::RemoveUserDelegate* delegate) OVERRIDE;
+  virtual bool IsDemoApp(const std::string& user_id) const OVERRIDE;
+  virtual bool IsKioskApp(const std::string& user_id) const OVERRIDE;
+  virtual bool IsPublicAccountMarkedForRemoval(
+      const std::string& user_id) const OVERRIDE;
+  virtual void DemoAccountLoggedIn() OVERRIDE;
+  virtual void GuestUserLoggedIn() OVERRIDE;
+  virtual void KioskAppLoggedIn(const std::string& app_id) OVERRIDE;
+  virtual void PublicAccountUserLoggedIn(user_manager::User* user) OVERRIDE;
+  virtual void RegularUserLoggedIn(const std::string& user_id) OVERRIDE;
+  virtual void RegularUserLoggedInAsEphemeral(
+      const std::string& user_id) OVERRIDE;
+  virtual void RetailModeUserLoggedIn() OVERRIDE;
+  virtual void SupervisedUserLoggedIn(const std::string& user_id) OVERRIDE;
+
+ private:
+  friend class SupervisedUserManagerImpl;
+  friend class UserManagerTest;
+  friend class WallpaperManager;
+  friend class WallpaperManagerTest;
+
+  typedef base::hash_map<std::string, linked_ptr<UserImageManager> >
+      UserImageManagerMap;
+
+  ChromeUserManagerImpl();
+
+  // Retrieves trusted device policies and removes users from the persistent
+  // list if ephemeral users are enabled. Schedules a callback to itself if
+  // trusted device policies are not yet available.
+  void RetrieveTrustedDevicePolicies();
+
+  // Updates current user ownership on UI thread.
+  void UpdateOwnership();
+
+  // If data for a public account is marked as pending removal and the user is
+  // no longer logged into that account, removes the data.
+  void CleanUpPublicAccountNonCryptohomeDataPendingRemoval();
+
+  // Removes data belonging to public accounts that are no longer found on the
+  // user list. If the user is currently logged into one of these accounts, the
+  // data for that account is not removed immediately but marked as pending
+  // removal after logout.
+  void CleanUpPublicAccountNonCryptohomeData(
+      const std::vector<std::string>& old_public_accounts);
+
+  // Replaces the list of public accounts with those found in
+  // |device_local_accounts|. Ensures that data belonging to accounts no longer
+  // on the list is removed. Returns |true| if the list has changed.
+  // Public accounts are defined by policy. This method is called whenever an
+  // updated list of public accounts is received from policy.
+  bool UpdateAndCleanUpPublicAccounts(
+      const std::vector<policy::DeviceLocalAccount>& device_local_accounts);
+
+  // Updates the display name for public account |username| from policy settings
+  // associated with that username.
+  void UpdatePublicAccountDisplayName(const std::string& user_id);
+
+  // Notifies the UI about a change to the user list.
+  void NotifyUserListChanged();
+
+  // Lazily creates default user flow.
+  UserFlow* GetDefaultUserFlow() const;
+
+  // MultiProfileUserControllerDelegate implementation:
+  virtual void OnUserNotAllowed(const std::string& user_email) OVERRIDE;
+
+  // Update the number of users.
+  void UpdateNumberOfUsers();
+
+  // Interface to the signed settings store.
+  CrosSettings* cros_settings_;
+
+  // Interface to device-local account definitions and associated policy.
+  policy::DeviceLocalAccountPolicyService* device_local_account_policy_service_;
+
+  content::NotificationRegistrar registrar_;
+
+  // User avatar managers.
+  UserImageManagerMap user_image_managers_;
+
+  // Supervised user manager.
+  scoped_ptr<SupervisedUserManagerImpl> supervised_user_manager_;
+
+  // Session length limiter.
+  scoped_ptr<SessionLengthLimiter> session_length_limiter_;
+
+  typedef std::map<std::string, UserFlow*> FlowMap;
+
+  // Lazy-initialized default flow.
+  mutable scoped_ptr<UserFlow> default_flow_;
+
+  // Specific flows by user e-mail. Keys should be canonicalized before
+  // access.
+  FlowMap specific_flows_;
+
+  scoped_ptr<CrosSettings::ObserverSubscription> local_accounts_subscription_;
+
+  scoped_ptr<MultiProfileUserController> multi_profile_user_controller_;
+
+  // Observer for the policy that can be used to manage user images.
+  scoped_ptr<policy::CloudExternalDataPolicyObserver> avatar_policy_observer_;
+
+  // Observer for the policy that can be used to manage wallpapers.
+  scoped_ptr<policy::CloudExternalDataPolicyObserver>
+      wallpaper_policy_observer_;
+
+  base::WeakPtrFactory<ChromeUserManagerImpl> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(ChromeUserManagerImpl);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_CHROME_USER_MANAGER_IMPL_H_
diff --git a/chrome/browser/chromeos/login/users/fake_user_manager.cc b/chrome/browser/chromeos/login/users/fake_user_manager.cc
index a969521..f801f8b 100644
--- a/chrome/browser/chromeos/login/users/fake_user_manager.cc
+++ b/chrome/browser/chromeos/login/users/fake_user_manager.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
 
+#include "base/task_runner.h"
 #include "chrome/browser/chromeos/login/users/fake_supervised_user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/grit/theme_resources.h"
@@ -16,12 +17,27 @@ namespace {
 // As defined in /chromeos/dbus/cryptohome_client.cc.
 static const char kUserIdHashSuffix[] = "-hash";
 
+class FakeTaskRunner : public base::TaskRunner {
+ public:
+  virtual bool PostDelayedTask(const tracked_objects::Location& from_here,
+                               const base::Closure& task,
+                               base::TimeDelta delay) OVERRIDE {
+    task.Run();
+    return true;
+  }
+  virtual bool RunsTasksOnCurrentThread() const OVERRIDE { return true; }
+
+ protected:
+  virtual ~FakeTaskRunner() {}
+};
+
 }  // namespace
 
 namespace chromeos {
 
 FakeUserManager::FakeUserManager()
-    : supervised_user_manager_(new FakeSupervisedUserManager),
+    : ChromeUserManager(new FakeTaskRunner(), new FakeTaskRunner()),
+      supervised_user_manager_(new FakeSupervisedUserManager),
       primary_user_(NULL),
       multi_profile_user_controller_(NULL) {
   ProfileHelper::SetProfileToUserForTestingEnabled(true);
@@ -304,4 +320,34 @@ bool FakeUserManager::AreSupervisedUsersAllowed() const {
   return true;
 }
 
+bool FakeUserManager::AreEphemeralUsersEnabled() const {
+  return false;
+}
+
+const std::string& FakeUserManager::GetApplicationLocale() const {
+  static const std::string default_locale("en-US");
+  return default_locale;
+}
+
+PrefService* FakeUserManager::GetLocalState() const {
+  return NULL;
+}
+
+bool FakeUserManager::IsEnterpriseManaged() const {
+  return false;
+}
+
+bool FakeUserManager::IsDemoApp(const std::string& user_id) const {
+  return false;
+}
+
+bool FakeUserManager::IsKioskApp(const std::string& user_id) const {
+  return false;
+}
+
+bool FakeUserManager::IsPublicAccountMarkedForRemoval(
+    const std::string& user_id) const {
+  return false;
+}
+
 }  // namespace chromeos
diff --git a/chrome/browser/chromeos/login/users/fake_user_manager.h b/chrome/browser/chromeos/login/users/fake_user_manager.h
index 8ade4ec..c312880 100644
--- a/chrome/browser/chromeos/login/users/fake_user_manager.h
+++ b/chrome/browser/chromeos/login/users/fake_user_manager.h
@@ -10,7 +10,7 @@
 
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/chromeos/login/user_flow.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "components/user_manager/user.h"
 #include "components/user_manager/user_image/user_image.h"
 
@@ -20,7 +20,7 @@ class FakeSupervisedUserManager;
 
 // Fake user manager with a barebones implementation. Users can be added
 // and set as logged in, and those users can be returned.
-class FakeUserManager : public UserManager {
+class FakeUserManager : public ChromeUserManager {
  public:
   FakeUserManager();
   virtual ~FakeUserManager();
@@ -37,6 +37,16 @@ class FakeUserManager : public UserManager {
   // Calculates the user name hash and calls UserLoggedIn to login a user.
   void LoginUser(const std::string& email);
 
+  // ChromeUserManager overrides.
+  virtual MultiProfileUserController* GetMultiProfileUserController() OVERRIDE;
+  virtual UserImageManager* GetUserImageManager(
+      const std::string& user_id) OVERRIDE;
+  virtual SupervisedUserManager* GetSupervisedUserManager() OVERRIDE;
+  virtual void SetUserFlow(const std::string& email, UserFlow* flow) OVERRIDE {}
+  virtual UserFlow* GetCurrentUserFlow() const OVERRIDE;
+  virtual UserFlow* GetUserFlow(const std::string& email) const OVERRIDE;
+  virtual void ResetUserFlow(const std::string& email) OVERRIDE {}
+
   // UserManager overrides.
   virtual const user_manager::UserList& GetUsers() const OVERRIDE;
   virtual user_manager::UserList GetUsersAdmittedForMultiProfile()
@@ -59,16 +69,13 @@ class FakeUserManager : public UserManager {
       const std::string& user_id,
       const UserAccountData& account_data) OVERRIDE {}
   virtual void Shutdown() OVERRIDE {}
-  virtual MultiProfileUserController* GetMultiProfileUserController() OVERRIDE;
-  virtual UserImageManager* GetUserImageManager(
-      const std::string& user_id) OVERRIDE;
-  virtual SupervisedUserManager* GetSupervisedUserManager() OVERRIDE;
   virtual const user_manager::UserList& GetLRULoggedInUsers() const OVERRIDE;
   virtual user_manager::UserList GetUnlockUsers() const OVERRIDE;
   virtual const std::string& GetOwnerEmail() const OVERRIDE;
   virtual void SessionStarted() OVERRIDE {}
   virtual void RemoveUser(const std::string& email,
-      RemoveUserDelegate* delegate) OVERRIDE {}
+                          user_manager::RemoveUserDelegate* delegate) OVERRIDE {
+  }
   virtual void RemoveUserFromList(const std::string& email) OVERRIDE;
   virtual bool IsKnownUser(const std::string& email) const OVERRIDE;
   virtual const user_manager::User* FindUser(
@@ -104,10 +111,6 @@ class FakeUserManager : public UserManager {
   virtual bool IsSessionStarted() const OVERRIDE;
   virtual bool IsUserNonCryptohomeDataEphemeral(
       const std::string& email) const OVERRIDE;
-  virtual void SetUserFlow(const std::string& email, UserFlow* flow) OVERRIDE {}
-  virtual UserFlow* GetCurrentUserFlow() const OVERRIDE;
-  virtual UserFlow* GetUserFlow(const std::string& email) const OVERRIDE;
-  virtual void ResetUserFlow(const std::string& email) OVERRIDE {}
   virtual void AddObserver(Observer* obs) OVERRIDE {}
   virtual void RemoveObserver(Observer* obs) OVERRIDE {}
   virtual void AddSessionStateObserver(
@@ -117,6 +120,29 @@ class FakeUserManager : public UserManager {
   virtual void NotifyLocalStateChanged() OVERRIDE {}
   virtual bool AreSupervisedUsersAllowed() const OVERRIDE;
 
+  // UserManagerBase overrides:
+  virtual bool AreEphemeralUsersEnabled() const OVERRIDE;
+  virtual const std::string& GetApplicationLocale() const OVERRIDE;
+  virtual PrefService* GetLocalState() const OVERRIDE;
+  virtual void HandleUserOAuthTokenStatusChange(
+      const std::string& user_id,
+      user_manager::User::OAuthTokenStatus status) const OVERRIDE {}
+  virtual bool IsEnterpriseManaged() const OVERRIDE;
+  virtual void LoadPublicAccounts(
+      std::set<std::string>* public_sessions_set) OVERRIDE {}
+  virtual void PerformPreUserListLoadingActions() OVERRIDE {}
+  virtual void PerformPostUserListLoadingActions() OVERRIDE {}
+  virtual void PerformPostUserLoggedInActions(bool browser_restart) OVERRIDE {}
+  virtual bool IsDemoApp(const std::string& user_id) const OVERRIDE;
+  virtual bool IsKioskApp(const std::string& user_id) const OVERRIDE;
+  virtual bool IsPublicAccountMarkedForRemoval(
+      const std::string& user_id) const OVERRIDE;
+  virtual void DemoAccountLoggedIn() OVERRIDE {}
+  virtual void KioskAppLoggedIn(const std::string& app_id) OVERRIDE {}
+  virtual void PublicAccountUserLoggedIn(user_manager::User* user) OVERRIDE {}
+  virtual void RetailModeUserLoggedIn() OVERRIDE {}
+  virtual void SupervisedUserLoggedIn(const std::string& user_id) OVERRIDE {}
+
   void set_owner_email(const std::string& owner_email) {
     owner_email_ = owner_email;
   }
diff --git a/chrome/browser/chromeos/login/users/mock_user_manager.cc b/chrome/browser/chromeos/login/users/mock_user_manager.cc
index a283a67..b459256 100644
--- a/chrome/browser/chromeos/login/users/mock_user_manager.cc
+++ b/chrome/browser/chromeos/login/users/mock_user_manager.cc
@@ -4,13 +4,33 @@
 
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
 
+#include "base/task_runner.h"
 #include "chrome/browser/chromeos/login/users/fake_supervised_user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 
+namespace {
+
+class FakeTaskRunner : public base::TaskRunner {
+ public:
+  virtual bool PostDelayedTask(const tracked_objects::Location& from_here,
+                               const base::Closure& task,
+                               base::TimeDelta delay) OVERRIDE {
+    task.Run();
+    return true;
+  }
+  virtual bool RunsTasksOnCurrentThread() const OVERRIDE { return true; }
+
+ protected:
+  virtual ~FakeTaskRunner() {}
+};
+
+}  // namespace
+
 namespace chromeos {
 
 MockUserManager::MockUserManager()
-    : user_flow_(new DefaultUserFlow()),
+    : ChromeUserManager(new FakeTaskRunner(), new FakeTaskRunner()),
+      user_flow_(new DefaultUserFlow()),
       supervised_user_manager_(new FakeSupervisedUserManager()) {
   ProfileHelper::SetProfileToUserForTestingEnabled(true);
 }
diff --git a/chrome/browser/chromeos/login/users/mock_user_manager.h b/chrome/browser/chromeos/login/users/mock_user_manager.h
index a5ad8de..7e8dc33 100644
--- a/chrome/browser/chromeos/login/users/mock_user_manager.h
+++ b/chrome/browser/chromeos/login/users/mock_user_manager.h
@@ -11,7 +11,7 @@
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/chromeos/login/user_flow.h"
 #include "chrome/browser/chromeos/login/users/avatar/mock_user_image_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "components/user_manager/user.h"
 #include "components/user_manager/user_image/user_image.h"
 #include "testing/gmock/include/gmock/gmock.h"
@@ -20,7 +20,7 @@ namespace chromeos {
 
 class FakeSupervisedUserManager;
 
-class MockUserManager : public UserManager {
+class MockUserManager : public ChromeUserManager {
  public:
   MockUserManager();
   virtual ~MockUserManager();
@@ -34,7 +34,8 @@ class MockUserManager : public UserManager {
       const std::string&, const std::string&, bool));
   MOCK_METHOD1(SwitchActiveUser, void(const std::string& email));
   MOCK_METHOD0(SessionStarted, void(void));
-  MOCK_METHOD2(RemoveUser, void(const std::string&, RemoveUserDelegate*));
+  MOCK_METHOD2(RemoveUser,
+               void(const std::string&, user_manager::RemoveUserDelegate*));
   MOCK_METHOD1(RemoveUserFromList, void(const std::string&));
   MOCK_CONST_METHOD1(IsKnownUser, bool(const std::string&));
   MOCK_CONST_METHOD1(FindUser, const user_manager::User*(const std::string&));
@@ -72,11 +73,29 @@ class MockUserManager : public UserManager {
   MOCK_METHOD1(RemoveSessionStateObserver,
                void(UserManager::UserSessionStateObserver*));
   MOCK_METHOD0(NotifyLocalStateChanged, void(void));
-  MOCK_METHOD2(SetUserFlow, void(const std::string&, UserFlow*));
-  MOCK_METHOD1(ResetUserFlow, void(const std::string&));
-
   MOCK_CONST_METHOD0(AreSupervisedUsersAllowed, bool(void));
 
+  // UserManagerBase overrides:
+  MOCK_CONST_METHOD0(AreEphemeralUsersEnabled, bool(void));
+  MOCK_CONST_METHOD0(GetApplicationLocale, const std::string&(void));
+  MOCK_CONST_METHOD0(GetLocalState, PrefService*(void));
+  MOCK_CONST_METHOD2(HandleUserOAuthTokenStatusChange,
+                     void(const std::string&,
+                          user_manager::User::OAuthTokenStatus status));
+  MOCK_CONST_METHOD0(IsEnterpriseManaged, bool(void));
+  MOCK_METHOD1(LoadPublicAccounts, void(std::set<std::string>*));
+  MOCK_METHOD0(PerformPreUserListLoadingActions, void(void));
+  MOCK_METHOD0(PerformPostUserListLoadingActions, void(void));
+  MOCK_METHOD1(PerformPostUserLoggedInActions, void(bool));
+  MOCK_CONST_METHOD1(IsDemoApp, bool(const std::string&));
+  MOCK_CONST_METHOD1(IsKioskApp, bool(const std::string&));
+  MOCK_CONST_METHOD1(IsPublicAccountMarkedForRemoval, bool(const std::string&));
+  MOCK_METHOD0(DemoAccountLoggedIn, void(void));
+  MOCK_METHOD1(KioskAppLoggedIn, void(const std::string&));
+  MOCK_METHOD1(PublicAccountUserLoggedIn, void(user_manager::User*));
+  MOCK_METHOD0(RetailModeUserLoggedIn, void(void));
+  MOCK_METHOD1(SupervisedUserLoggedIn, void(const std::string&));
+
   // You can't mock these functions easily because nobody can create
   // User objects but the ChromeUserManager and us.
   virtual const user_manager::UserList& GetUsers() const OVERRIDE;
@@ -88,11 +107,13 @@ class MockUserManager : public UserManager {
   virtual user_manager::User* GetActiveUser() OVERRIDE;
   virtual const user_manager::User* GetPrimaryUser() const OVERRIDE;
 
+  // ChromeUserManager overrides:
   virtual MultiProfileUserController* GetMultiProfileUserController() OVERRIDE;
   virtual UserImageManager* GetUserImageManager(
       const std::string& user_id) OVERRIDE;
   virtual SupervisedUserManager* GetSupervisedUserManager() OVERRIDE;
-
+  MOCK_METHOD2(SetUserFlow, void(const std::string&, UserFlow*));
+  MOCK_METHOD1(ResetUserFlow, void(const std::string&));
   virtual UserFlow* GetCurrentUserFlow() const OVERRIDE;
   virtual UserFlow* GetUserFlow(const std::string&) const OVERRIDE;
 
diff --git a/chrome/browser/chromeos/login/users/multi_profile_user_controller.cc b/chrome/browser/chromeos/login/users/multi_profile_user_controller.cc
index d079360..f328c2c 100644
--- a/chrome/browser/chromeos/login/users/multi_profile_user_controller.cc
+++ b/chrome/browser/chromeos/login/users/multi_profile_user_controller.cc
@@ -11,7 +11,6 @@
 #include "base/prefs/pref_service.h"
 #include "base/prefs/scoped_user_pref_update.h"
 #include "chrome/browser/chromeos/login/users/multi_profile_user_controller_delegate.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/policy_cert_service.h"
 #include "chrome/browser/chromeos/policy/policy_cert_service_factory.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
@@ -19,6 +18,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/pref_names.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 
 namespace chromeos {
@@ -90,7 +90,7 @@ void MultiProfileUserController::RegisterProfilePrefs(
 // static
 MultiProfileUserController::UserAllowedInSessionReason
 MultiProfileUserController::GetPrimaryUserPolicy() {
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   CHECK(user_manager);
 
   const user_manager::User* user = user_manager->GetPrimaryUser();
@@ -129,7 +129,7 @@ MultiProfileUserController::GetPrimaryUserPolicy() {
 bool MultiProfileUserController::IsUserAllowedInSession(
     const std::string& user_email,
     MultiProfileUserController::UserAllowedInSessionReason* reason) const {
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   CHECK(user_manager);
 
   const user_manager::User* primary_user = user_manager->GetPrimaryUser();
@@ -208,7 +208,8 @@ void MultiProfileUserController::SetCachedValue(
 }
 
 void MultiProfileUserController::CheckSessionUsers() {
-  const user_manager::UserList& users = UserManager::Get()->GetLoggedInUsers();
+  const user_manager::UserList& users =
+      user_manager::UserManager::Get()->GetLoggedInUsers();
   for (user_manager::UserList::const_iterator it = users.begin();
        it != users.end();
        ++it) {
diff --git a/chrome/browser/chromeos/login/users/multi_profile_user_controller_unittest.cc b/chrome/browser/chromeos/login/users/multi_profile_user_controller_unittest.cc
index b93d73a..7bf7b94 100644
--- a/chrome/browser/chromeos/login/users/multi_profile_user_controller_unittest.cc
+++ b/chrome/browser/chromeos/login/users/multi_profile_user_controller_unittest.cc
@@ -9,7 +9,7 @@
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
 #include "chrome/browser/chromeos/login/users/multi_profile_user_controller_delegate.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/policy/policy_cert_service.h"
 #include "chrome/browser/chromeos/policy/policy_cert_service_factory.h"
 #include "chrome/browser/chromeos/policy/policy_cert_verifier.h"
@@ -21,6 +21,7 @@
 #include "chrome/test/base/testing_pref_service_syncable.h"
 #include "chrome/test/base/testing_profile.h"
 #include "chrome/test/base/testing_profile_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/test/test_browser_thread_bundle.h"
 #include "net/cert/x509_certificate.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -101,8 +102,9 @@ policy::PolicyCertVerifier* g_policy_cert_verifier_for_factory = NULL;
 
 KeyedService* TestPolicyCertServiceFactory(content::BrowserContext* context) {
   return policy::PolicyCertService::CreateForTesting(
-      kUsers[0], g_policy_cert_verifier_for_factory, UserManager::Get())
-      .release();
+             kUsers[0],
+             g_policy_cert_verifier_for_factory,
+             user_manager::UserManager::Get()).release();
 }
 
 }  // namespace
diff --git a/chrome/browser/chromeos/login/users/scoped_test_user_manager.cc b/chrome/browser/chromeos/login/users/scoped_test_user_manager.cc
new file mode 100644
index 0000000..49dc7f2
--- /dev/null
+++ b/chrome/browser/chromeos/login/users/scoped_test_user_manager.cc
@@ -0,0 +1,26 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
+
+#include "chrome/browser/chromeos/login/users/chrome_user_manager_impl.h"
+#include "chrome/browser/chromeos/profiles/profile_helper.h"
+
+namespace chromeos {
+
+ScopedTestUserManager::ScopedTestUserManager() {
+  chrome_user_manager_ = ChromeUserManagerImpl::CreateChromeUserManager();
+  chrome_user_manager_->Initialize();
+
+  // ProfileHelper has to be initialized after UserManager instance is created.
+  ProfileHelper::Get()->Initialize();
+}
+
+ScopedTestUserManager::~ScopedTestUserManager() {
+  user_manager::UserManager::Get()->Shutdown();
+  chrome_user_manager_->Destroy();
+  chrome_user_manager_.reset();
+}
+
+}  // namespace chromeos
diff --git a/chrome/browser/chromeos/login/users/scoped_test_user_manager.h b/chrome/browser/chromeos/login/users/scoped_test_user_manager.h
new file mode 100644
index 0000000..ec07d2c
--- /dev/null
+++ b/chrome/browser/chromeos/login/users/scoped_test_user_manager.h
@@ -0,0 +1,30 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_CHROMEOS_LOGIN_USERS_SCOPED_TEST_USER_MANAGER_H_
+#define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_SCOPED_TEST_USER_MANAGER_H_
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace chromeos {
+
+class ChromeUserManager;
+
+// Helper class for unit tests. Initializes the UserManager singleton on
+// construction and tears it down again on destruction.
+class ScopedTestUserManager {
+ public:
+  ScopedTestUserManager();
+  ~ScopedTestUserManager();
+
+ private:
+  scoped_ptr<ChromeUserManager> chrome_user_manager_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedTestUserManager);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_SCOPED_TEST_USER_MANAGER_H_
diff --git a/chrome/browser/chromeos/login/users/scoped_user_manager_enabler.cc b/chrome/browser/chromeos/login/users/scoped_user_manager_enabler.cc
new file mode 100644
index 0000000..8ae87be
--- /dev/null
+++ b/chrome/browser/chromeos/login/users/scoped_user_manager_enabler.cc
@@ -0,0 +1,29 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
+
+#include "components/user_manager/user_manager.h"
+
+namespace chromeos {
+
+ScopedUserManagerEnabler::ScopedUserManagerEnabler(
+    user_manager::UserManager* user_manager) {
+  if (user_manager::UserManager::GetForTesting())
+    user_manager::UserManager::GetForTesting()->Shutdown();
+
+  previous_user_manager_ =
+      user_manager::UserManager::SetForTesting(user_manager);
+}
+
+ScopedUserManagerEnabler::~ScopedUserManagerEnabler() {
+  // Shutdown and destroy current UserManager instance that we track.
+  user_manager::UserManager::Get()->Shutdown();
+  delete user_manager::UserManager::Get();
+  user_manager::UserManager::SetInstance(NULL);
+
+  user_manager::UserManager::SetForTesting(previous_user_manager_);
+}
+
+}  // namespace chromeos
diff --git a/chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h b/chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h
new file mode 100644
index 0000000..38880f6
--- /dev/null
+++ b/chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h
@@ -0,0 +1,34 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_CHROMEOS_LOGIN_USERS_SCOPED_USER_MANAGER_ENABLER_H_
+#define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_SCOPED_USER_MANAGER_ENABLER_H_
+
+#include "base/basictypes.h"
+
+namespace user_manager {
+class UserManager;
+}
+
+namespace chromeos {
+
+// Helper class for unit tests. Initializes the UserManager singleton to the
+// given |user_manager| and tears it down again on destruction. If the singleton
+// had already been initialized, its previous value is restored after tearing
+// down |user_manager|.
+class ScopedUserManagerEnabler {
+ public:
+  // Takes ownership of |user_manager|.
+  explicit ScopedUserManagerEnabler(user_manager::UserManager* user_manager);
+  ~ScopedUserManagerEnabler();
+
+ private:
+  user_manager::UserManager* previous_user_manager_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedUserManagerEnabler);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_SCOPED_USER_MANAGER_ENABLER_H_
diff --git a/chrome/browser/chromeos/login/users/supervised_user_manager_impl.cc b/chrome/browser/chromeos/login/users/supervised_user_manager_impl.cc
index 7335a0a..1e4b1c3 100644
--- a/chrome/browser/chromeos/login/users/supervised_user_manager_impl.cc
+++ b/chrome/browser/chromeos/login/users/supervised_user_manager_impl.cc
@@ -17,7 +17,7 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_authentication.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_constants.h"
-#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager_impl.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/supervised_user/supervised_user_service.h"
 #include "chrome/browser/supervised_user/supervised_user_service_factory.h"
@@ -129,7 +129,8 @@ void SupervisedUserManager::RegisterPrefs(PrefRegistrySimple* registry) {
   registry->RegisterDictionaryPref(kSupervisedUserIncompleteKey);
 }
 
-SupervisedUserManagerImpl::SupervisedUserManagerImpl(ChromeUserManager* owner)
+SupervisedUserManagerImpl::SupervisedUserManagerImpl(
+    ChromeUserManagerImpl* owner)
     : owner_(owner), cros_settings_(CrosSettings::Get()) {
   // SupervisedUserManager instance should be used only on UI thread.
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
diff --git a/chrome/browser/chromeos/login/users/supervised_user_manager_impl.h b/chrome/browser/chromeos/login/users/supervised_user_manager_impl.h
index 05e45d4..eaa013f 100644
--- a/chrome/browser/chromeos/login/users/supervised_user_manager_impl.h
+++ b/chrome/browser/chromeos/login/users/supervised_user_manager_impl.h
@@ -14,7 +14,7 @@
 
 namespace chromeos {
 
-class ChromeUserManager;
+class ChromeUserManagerImpl;
 class CrosSettings;
 
 // Implementation of the UserManager.
@@ -60,10 +60,10 @@ class SupervisedUserManagerImpl
       const std::string& token) OVERRIDE;
 
  private:
-  friend class ChromeUserManager;
+  friend class ChromeUserManagerImpl;
   friend class UserManager;
 
-  explicit SupervisedUserManagerImpl(ChromeUserManager* owner);
+  explicit SupervisedUserManagerImpl(ChromeUserManagerImpl* owner);
 
   // Returns true if there is non-committed user creation transaction.
   bool HasFailedUserCreationTransaction();
@@ -106,7 +106,7 @@ class SupervisedUserManagerImpl
   void CleanPref(const std::string& user_id,
                  const char* key);
 
-  ChromeUserManager* owner_;
+  ChromeUserManagerImpl* owner_;
 
   // Interface to the signed settings store.
   CrosSettings* cros_settings_;
diff --git a/chrome/browser/chromeos/login/users/user_manager.cc b/chrome/browser/chromeos/login/users/user_manager.cc
deleted file mode 100644
index 1adceeb..0000000
--- a/chrome/browser/chromeos/login/users/user_manager.cc
+++ /dev/null
@@ -1,108 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "chrome/browser/chromeos/login/users/user_manager.h"
-
-#include "base/command_line.h"
-#include "base/prefs/pref_registry_simple.h"
-#include "chrome/browser/browser_process_platform_part_chromeos.h"
-#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
-#include "chrome/browser/chromeos/profiles/profile_helper.h"
-#include "chrome/common/chrome_switches.h"
-
-namespace chromeos {
-
-static UserManager* g_user_manager = NULL;
-
-UserManager::Observer::~Observer() {
-}
-
-void UserManager::Observer::LocalStateChanged(UserManager* user_manager) {
-}
-
-void UserManager::UserSessionStateObserver::ActiveUserChanged(
-    const user_manager::User* active_user) {
-}
-
-void UserManager::UserSessionStateObserver::UserAddedToSession(
-    const user_manager::User* active_user) {
-}
-
-void UserManager::UserSessionStateObserver::ActiveUserHashChanged(
-    const std::string& hash) {
-}
-
-UserManager::UserSessionStateObserver::~UserSessionStateObserver() {
-}
-
-UserManager::UserAccountData::UserAccountData(
-    const base::string16& display_name,
-    const base::string16& given_name,
-    const std::string& locale)
-    : display_name_(display_name),
-      given_name_(given_name),
-      locale_(locale) {
-}
-
-UserManager::UserAccountData::~UserAccountData() {}
-
-// static
-void UserManager::Initialize() {
-  CHECK(!g_user_manager);
-  g_user_manager = new ChromeUserManager();
-}
-
-// static
-bool UserManager::IsInitialized() {
-  return g_user_manager;
-}
-
-void UserManager::Destroy() {
-  DCHECK(g_user_manager);
-  delete g_user_manager;
-  g_user_manager = NULL;
-}
-
-// static
-UserManager* UserManager::Get() {
-  CHECK(g_user_manager);
-  return g_user_manager;
-}
-
-UserManager::~UserManager() {
-}
-
-// static
-UserManager* UserManager::SetForTesting(UserManager* user_manager) {
-  UserManager* previous_user_manager = g_user_manager;
-  if (previous_user_manager)
-    previous_user_manager->Shutdown();
-
-  g_user_manager = user_manager;
-  return previous_user_manager;
-}
-
-ScopedUserManagerEnabler::ScopedUserManagerEnabler(UserManager* user_manager)
-    : previous_user_manager_(UserManager::SetForTesting(user_manager)) {
-}
-
-ScopedUserManagerEnabler::~ScopedUserManagerEnabler() {
-  UserManager::Get()->Shutdown();
-  UserManager::Destroy();
-  UserManager::SetForTesting(previous_user_manager_);
-}
-
-ScopedTestUserManager::ScopedTestUserManager() {
-  UserManager::Initialize();
-
-  // ProfileHelper has to be initialized after UserManager instance is created.
-  ProfileHelper::Get()->Initialize();
-}
-
-ScopedTestUserManager::~ScopedTestUserManager() {
-  UserManager::Get()->Shutdown();
-  UserManager::Destroy();
-}
-
-}  // namespace chromeos
diff --git a/chrome/browser/chromeos/login/users/user_manager_unittest.cc b/chrome/browser/chromeos/login/users/user_manager_unittest.cc
index 20c8e44..5a3e989 100644
--- a/chrome/browser/chromeos/login/users/user_manager_unittest.cc
+++ b/chrome/browser/chromeos/login/users/user_manager_unittest.cc
@@ -12,8 +12,8 @@
 #include "base/run_loop.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager_impl.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #include "chrome/browser/chromeos/settings/stub_cros_settings_provider.h"
@@ -27,6 +27,7 @@
 #include "chromeos/settings/cros_settings_names.h"
 #include "chromeos/settings/cros_settings_provider.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/test/test_browser_thread_bundle.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -103,8 +104,9 @@ class UserManagerTest : public testing::Test {
     chromeos::DBusThreadManager::Shutdown();
   }
 
-  ChromeUserManager* GetChromeUserManager() const {
-    return static_cast<ChromeUserManager*>(UserManager::Get());
+  ChromeUserManagerImpl* GetChromeUserManager() const {
+    return static_cast<ChromeUserManagerImpl*>(
+        user_manager::UserManager::Get());
   }
 
   bool GetUserManagerEphemeralUsersEnabled() const {
@@ -126,12 +128,12 @@ class UserManagerTest : public testing::Test {
   void ResetUserManager() {
     // Reset the UserManager singleton.
     user_manager_enabler_.reset();
-    // Initialize the UserManager singleton to a fresh ChromeUserManager
+    // Initialize the UserManager singleton to a fresh ChromeUserManagerImpl
     // instance.
     user_manager_enabler_.reset(
-        new ScopedUserManagerEnabler(new ChromeUserManager));
+        new ScopedUserManagerEnabler(new ChromeUserManagerImpl));
 
-    // ChromeUserManager ctor posts a task to reload policies.
+    // ChromeUserManagerImpl ctor posts a task to reload policies.
     base::RunLoop().RunUntilIdle();
   }
 
@@ -179,17 +181,18 @@ TEST_F(UserManagerTest, RetrieveTrustedDevicePolicies) {
 }
 
 TEST_F(UserManagerTest, RemoveAllExceptOwnerFromList) {
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       "owner@invalid.domain", "owner@invalid.domain", false);
   ResetUserManager();
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       "user0@invalid.domain", "owner@invalid.domain", false);
   ResetUserManager();
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       "user1@invalid.domain", "owner@invalid.domain", false);
   ResetUserManager();
 
-  const user_manager::UserList* users = &UserManager::Get()->GetUsers();
+  const user_manager::UserList* users =
+      &user_manager::UserManager::Get()->GetUsers();
   ASSERT_EQ(3U, users->size());
   EXPECT_EQ((*users)[0]->email(), "user1@invalid.domain");
   EXPECT_EQ((*users)[1]->email(), "user0@invalid.domain");
@@ -198,7 +201,7 @@ TEST_F(UserManagerTest, RemoveAllExceptOwnerFromList) {
   SetDeviceSettings(true, "owner@invalid.domain", false);
   RetrieveTrustedDevicePolicies();
 
-  users = &UserManager::Get()->GetUsers();
+  users = &user_manager::UserManager::Get()->GetUsers();
   EXPECT_EQ(1U, users->size());
   EXPECT_EQ((*users)[0]->email(), "owner@invalid.domain");
 }
@@ -207,14 +210,15 @@ TEST_F(UserManagerTest, RegularUserLoggedInAsEphemeral) {
   SetDeviceSettings(true, "owner@invalid.domain", false);
   RetrieveTrustedDevicePolicies();
 
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       "owner@invalid.domain", "user0@invalid.domain", false);
   ResetUserManager();
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       "user0@invalid.domain", "user0@invalid.domain", false);
   ResetUserManager();
 
-  const user_manager::UserList* users = &UserManager::Get()->GetUsers();
+  const user_manager::UserList* users =
+      &user_manager::UserManager::Get()->GetUsers();
   EXPECT_EQ(1U, users->size());
   EXPECT_EQ((*users)[0]->email(), "owner@invalid.domain");
 }
diff --git a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.cc b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.cc
index 461c1b7..6053cee 100644
--- a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.cc
+++ b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.cc
@@ -34,7 +34,6 @@
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/customization_document.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/common/chrome_paths.h"
@@ -46,6 +45,7 @@
 #include "chromeos/login/user_names.h"
 #include "components/user_manager/user.h"
 #include "components/user_manager/user_image/user_image.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
@@ -536,7 +536,8 @@ void WallpaperManager::EnsureLoggedInUserWallpaperLoaded() {
     if (info == current_user_wallpaper_info_)
       return;
   }
-  SetUserWallpaperNow(UserManager::Get()->GetLoggedInUser()->email());
+  SetUserWallpaperNow(
+      user_manager::UserManager::Get()->GetLoggedInUser()->email());
 }
 
 void WallpaperManager::ClearDisposableWallpaperCache() {
@@ -545,7 +546,7 @@ void WallpaperManager::ClearDisposableWallpaperCache() {
   // Keep the wallpaper of logged in users in cache at multi-profile mode.
   std::set<std::string> logged_in_users_names;
   const user_manager::UserList& logged_users =
-      UserManager::Get()->GetLoggedInUsers();
+      user_manager::UserManager::Get()->GetLoggedInUsers();
   for (user_manager::UserList::const_iterator it = logged_users.begin();
        it != logged_users.end();
        ++it) {
@@ -566,7 +567,7 @@ void WallpaperManager::ClearDisposableWallpaperCache() {
 bool WallpaperManager::GetLoggedInUserWallpaperInfo(WallpaperInfo* info) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-  if (UserManager::Get()->IsLoggedInAsStub()) {
+  if (user_manager::UserManager::Get()->IsLoggedInAsStub()) {
     info->location = current_user_wallpaper_info_.location = "";
     info->layout = current_user_wallpaper_info_.layout =
         ash::WALLPAPER_LAYOUT_CENTER_CROPPED;
@@ -577,13 +578,13 @@ bool WallpaperManager::GetLoggedInUserWallpaperInfo(WallpaperInfo* info) {
     return true;
   }
 
-  return GetUserWallpaperInfo(UserManager::Get()->GetLoggedInUser()->email(),
-                              info);
+  return GetUserWallpaperInfo(
+      user_manager::UserManager::Get()->GetLoggedInUser()->email(), info);
 }
 
 void WallpaperManager::InitializeWallpaper() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
   // Apply device customization.
   if (ShouldUseCustomizedDefaultWallpaper()) {
@@ -828,7 +829,7 @@ void WallpaperManager::SetPolicyControlledWallpaper(
     const std::string& user_id,
     const user_manager::UserImage& user_image) {
   const user_manager::User* user =
-      chromeos::UserManager::Get()->FindUser(user_id);
+      user_manager::UserManager::Get()->FindUser(user_id);
   if (!user) {
     NOTREACHED() << "Unknown user.";
     return;
@@ -881,7 +882,7 @@ void WallpaperManager::SetCustomWallpaper(
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   // There is no visible background in kiosk mode.
-  if (UserManager::Get()->IsLoggedInAsKioskApp())
+  if (user_manager::UserManager::Get()->IsLoggedInAsKioskApp())
     return;
 
   // Don't allow custom wallpapers while policy is in effect.
@@ -898,10 +899,12 @@ void WallpaperManager::SetCustomWallpaper(
     return;
   }
 
-  const user_manager::User *user = UserManager::Get()->FindUser(user_id);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(user_id);
   CHECK(user);
   bool is_persistent =
-      !UserManager::Get()->IsUserNonCryptohomeDataEphemeral(user_id) ||
+      !user_manager::UserManager::Get()->IsUserNonCryptohomeDataEphemeral(
+          user_id) ||
       (type == user_manager::User::POLICY &&
        user->GetType() == user_manager::USER_TYPE_PUBLIC_ACCOUNT);
 
@@ -960,7 +963,7 @@ void WallpaperManager::DoSetDefaultWallpaper(
     const std::string& user_id,
     MovableOnDestroyCallbackHolder on_finish) {
   // There is no visible background in kiosk mode.
-  if (UserManager::Get()->IsLoggedInAsKioskApp())
+  if (user_manager::UserManager::Get()->IsLoggedInAsKioskApp())
     return;
   current_wallpaper_path_.clear();
   wallpaper_cache_.erase(user_id);
@@ -975,7 +978,7 @@ void WallpaperManager::DoSetDefaultWallpaper(
 
   const base::FilePath* file = NULL;
 
-  if (UserManager::Get()->IsLoggedInAsGuest()) {
+  if (user_manager::UserManager::Get()->IsLoggedInAsGuest()) {
     file =
         use_small ? &guest_small_wallpaper_file_ : &guest_large_wallpaper_file_;
   } else {
@@ -1167,21 +1170,26 @@ void WallpaperManager::ScheduleSetUserWallpaper(const std::string& user_id,
                                                 bool delayed) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   // Some unit tests come here without a UserManager or without a pref system.
-  if (!UserManager::IsInitialized() || !g_browser_process->local_state())
+  if (!user_manager::UserManager::IsInitialized() ||
+      !g_browser_process->local_state()) {
     return;
+  }
+
   // There is no visible background in kiosk mode.
-  if (UserManager::Get()->IsLoggedInAsKioskApp())
+  if (user_manager::UserManager::Get()->IsLoggedInAsKioskApp())
     return;
   // Guest user, regular user in ephemeral mode, or kiosk app.
-  const user_manager::User* user = UserManager::Get()->FindUser(user_id);
-  if (UserManager::Get()->IsUserNonCryptohomeDataEphemeral(user_id) ||
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(user_id);
+  if (user_manager::UserManager::Get()->IsUserNonCryptohomeDataEphemeral(
+          user_id) ||
       (user != NULL && user->GetType() == user_manager::USER_TYPE_KIOSK_APP)) {
     InitInitialUserWallpaper(user_id, false);
     GetPendingWallpaper(user_id, delayed)->ResetSetDefaultWallpaper();
     return;
   }
 
-  if (!UserManager::Get()->IsKnownUser(user_id))
+  if (!user_manager::UserManager::Get()->IsKnownUser(user_id))
     return;
 
   last_selected_user_ = user_id;
@@ -1235,10 +1243,10 @@ void WallpaperManager::SetWallpaperFromImageSkia(const std::string& user_id,
                                                  const gfx::ImageSkia& image,
                                                  ash::WallpaperLayout layout,
                                                  bool update_wallpaper) {
-  DCHECK(UserManager::Get()->IsUserLoggedIn());
+  DCHECK(user_manager::UserManager::Get()->IsUserLoggedIn());
 
   // There is no visible background in kiosk mode.
-  if (UserManager::Get()->IsLoggedInAsKioskApp())
+  if (user_manager::UserManager::Get()->IsLoggedInAsKioskApp())
     return;
   WallpaperInfo info;
   info.layout = layout;
@@ -1294,7 +1302,7 @@ bool WallpaperManager::GetWallpaperFromCache(const std::string& user_id,
 
 void WallpaperManager::CacheUsersWallpapers() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  user_manager::UserList users = UserManager::Get()->GetUsers();
+  user_manager::UserList users = user_manager::UserManager::Get()->GetUsers();
 
   if (!users.empty()) {
     user_manager::UserList::const_iterator it = users.begin();
@@ -1399,7 +1407,7 @@ CommandLine* WallpaperManager::GetCommandLine() {
 }
 
 void WallpaperManager::InitializeRegisteredDeviceWallpaper() {
-  if (UserManager::Get()->IsUserLoggedIn())
+  if (user_manager::UserManager::Get()->IsUserLoggedIn())
     return;
 
   bool disable_boot_animation =
@@ -1409,7 +1417,8 @@ void WallpaperManager::InitializeRegisteredDeviceWallpaper() {
       kAccountsPrefShowUserNamesOnSignIn, &show_users);
   DCHECK(result) << "Unable to fetch setting "
                  << kAccountsPrefShowUserNamesOnSignIn;
-  const user_manager::UserList& users = UserManager::Get()->GetUsers();
+  const user_manager::UserList& users =
+      user_manager::UserManager::Get()->GetUsers();
   int public_session_user_index = FindPublicSession(users);
   if ((!show_users && public_session_user_index == -1) || users.empty()) {
     // Boot into sign in form, preload default wallpaper.
@@ -1494,7 +1503,8 @@ bool WallpaperManager::GetUserWallpaperInfo(const std::string& user_id,
                                             WallpaperInfo* info) const {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-  if (UserManager::Get()->IsUserNonCryptohomeDataEphemeral(user_id)) {
+  if (user_manager::UserManager::Get()->IsUserNonCryptohomeDataEphemeral(
+          user_id)) {
     // Default to the values cached in memory.
     *info = current_user_wallpaper_info_;
 
@@ -1544,20 +1554,23 @@ void WallpaperManager::MoveCustomWallpapersSuccess(
     // This is needed because at login screen, user id hash is not available.
     info.location = base::FilePath(user_id_hash).Append(info.location).value();
     bool is_persistent =
-        !UserManager::Get()->IsUserNonCryptohomeDataEphemeral(user_id);
+        !user_manager::UserManager::Get()->IsUserNonCryptohomeDataEphemeral(
+            user_id);
     SetUserWallpaperInfo(user_id, info, is_persistent);
   }
 }
 
 void WallpaperManager::MoveLoggedInUserCustomWallpaper() {
   const user_manager::User* logged_in_user =
-      UserManager::Get()->GetLoggedInUser();
-  task_runner_->PostTask(
-      FROM_HERE,
-      base::Bind(&WallpaperManager::MoveCustomWallpapersOnWorker,
-                 logged_in_user->email(),
-                 logged_in_user->username_hash(),
-                 weak_factory_.GetWeakPtr()));
+      user_manager::UserManager::Get()->GetLoggedInUser();
+  if (logged_in_user) {
+    task_runner_->PostTask(
+        FROM_HERE,
+        base::Bind(&WallpaperManager::MoveCustomWallpapersOnWorker,
+                   logged_in_user->email(),
+                   logged_in_user->username_hash(),
+                   weak_factory_.GetWeakPtr()));
+  }
 }
 
 void WallpaperManager::OnWallpaperDecoded(
diff --git a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_browsertest.cc b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_browsertest.cc
index 2b11522..46f75a9 100644
--- a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_browsertest.cc
+++ b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_browsertest.cc
@@ -24,7 +24,6 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/time/time.h"
 #include "base/values.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/test/base/in_process_browser_test.h"
@@ -32,6 +31,7 @@
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/login/user_names.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/test/test_utils.h"
 #include "ui/aura/env.h"
 #include "ui/gfx/image/image_skia.h"
@@ -111,7 +111,8 @@ class WallpaperManagerBrowserTest : public InProcessBrowserTest {
 
   // Logs in |username|.
   void LogIn(const std::string& username, const std::string& username_hash) {
-    UserManager::Get()->UserLoggedIn(username, username_hash, false);
+    user_manager::UserManager::Get()->UserLoggedIn(
+        username, username_hash, false);
     WaitAsyncWallpaperLoadStarted();
   }
 
@@ -733,7 +734,7 @@ IN_PROC_BROWSER_TEST_F(WallpaperManagerBrowserTest, SmallGuestWallpaper) {
   if (!ash::test::AshTestHelper::SupportsMultipleDisplays())
     return;
   CreateCmdlineWallpapers();
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       chromeos::login::kGuestUserName, chromeos::login::kGuestUserName, false);
   UpdateDisplay("800x600");
   WallpaperManager::Get()->SetDefaultWallpaperNow(std::string());
@@ -748,7 +749,7 @@ IN_PROC_BROWSER_TEST_F(WallpaperManagerBrowserTest, LargeGuestWallpaper) {
     return;
 
   CreateCmdlineWallpapers();
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       chromeos::login::kGuestUserName, chromeos::login::kGuestUserName, false);
   UpdateDisplay("1600x1200");
   WallpaperManager::Get()->SetDefaultWallpaperNow(std::string());
@@ -763,7 +764,7 @@ IN_PROC_BROWSER_TEST_F(WallpaperManagerBrowserTest,
   // Start loading the default wallpaper.
   UpdateDisplay("640x480");
   CreateCmdlineWallpapers();
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       chromeos::login::kStubUser, "test_hash", false);
 
   WallpaperManager::Get()->SetDefaultWallpaperNow(std::string());
diff --git a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_policy_browsertest.cc b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_policy_browsertest.cc
index 506f5c5..7abb4bb 100644
--- a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_policy_browsertest.cc
+++ b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_policy_browsertest.cc
@@ -20,7 +20,6 @@
 #include "chrome/browser/chromeos/login/login_manager_test.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/chromeos/policy/cloud_external_data_manager_base_test_util.h"
 #include "chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos.h"
@@ -40,6 +39,7 @@
 #include "components/policy/core/common/cloud/cloud_policy_validator.h"
 #include "components/policy/core/common/cloud/policy_builder.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/test/browser_test_utils.h"
 #include "crypto/rsa_private_key.h"
 #include "net/test/embedded_test_server/embedded_test_server.h"
@@ -245,7 +245,8 @@ class WallpaperManagerPolicyTest
     }
     builder->Build();
     fake_session_manager_client_->set_user_policy(user_id, builder->GetBlob());
-    const user_manager::User* user = UserManager::Get()->FindUser(user_id);
+    const user_manager::User* user =
+        user_manager::UserManager::Get()->FindUser(user_id);
     ASSERT_TRUE(user);
     policy::CloudPolicyStore* store = GetStoreForUser(user);
     ASSERT_TRUE(store);
diff --git a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_unittest.cc b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_unittest.cc
index 9e6d4a5..06c97ed 100644
--- a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_unittest.cc
+++ b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_unittest.cc
@@ -20,6 +20,7 @@
 #include "base/prefs/testing_pref_service.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
diff --git a/chrome/browser/chromeos/login/wizard_controller.cc b/chrome/browser/chromeos/login/wizard_controller.cc
index 9ba3c1b4..bba472f 100644
--- a/chrome/browser/chromeos/login/wizard_controller.cc
+++ b/chrome/browser/chromeos/login/wizard_controller.cc
@@ -49,7 +49,6 @@
 #include "chrome/browser/chromeos/login/supervised/supervised_user_creation_screen.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host.h"
 #include "chrome/browser/chromeos/login/ui/oobe_display.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/net/delay_network_call.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_cloud_policy_initializer.h"
@@ -73,6 +72,7 @@
 #include "chromeos/settings/cros_settings_names.h"
 #include "chromeos/settings/timezone_settings.h"
 #include "components/breakpad/app/breakpad_linux.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_types.h"
 #include "ui/base/accelerators/accelerator.h"
@@ -444,7 +444,8 @@ void WizardController::ShowUpdateScreen() {
 }
 
 void WizardController::ShowUserImageScreen() {
-  const chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  const user_manager::UserManager* user_manager =
+      user_manager::UserManager::Get();
   // Skip user image selection for public sessions and ephemeral logins.
   if (user_manager->IsLoggedInAsPublicAccount() ||
       user_manager->IsCurrentUserNonCryptohomeDataEphemeral()) {
@@ -518,9 +519,9 @@ void WizardController::ShowTermsOfServiceScreen() {
   // Only show the Terms of Service when logging into a public account and Terms
   // of Service have been specified through policy. In all other cases, advance
   // to the user image screen immediately.
-  if (!chromeos::UserManager::Get()->IsLoggedInAsPublicAccount() ||
-      !ProfileManager::GetActiveUserProfile()->GetPrefs()->
-          IsManagedPreference(prefs::kTermsOfServiceURL)) {
+  if (!user_manager::UserManager::Get()->IsLoggedInAsPublicAccount() ||
+      !ProfileManager::GetActiveUserProfile()->GetPrefs()->IsManagedPreference(
+          prefs::kTermsOfServiceURL)) {
     ShowUserImageScreen();
     return;
   }
diff --git a/chrome/browser/chromeos/net/onc_utils.cc b/chrome/browser/chromeos/net/onc_utils.cc
index febfac2..dae67a2 100644
--- a/chrome/browser/chromeos/net/onc_utils.cc
+++ b/chrome/browser/chromeos/net/onc_utils.cc
@@ -9,7 +9,6 @@
 #include "base/logging.h"
 #include "base/prefs/pref_service.h"
 #include "base/values.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/ui_proxy_config.h"
 #include "chrome/browser/prefs/proxy_config_dictionary.h"
 #include "chrome/common/pref_names.h"
@@ -26,6 +25,7 @@
 #include "chromeos/network/onc/onc_translator.h"
 #include "chromeos/network/onc/onc_utils.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "net/base/host_port_pair.h"
 #include "net/proxy/proxy_bypass_rules.h"
 #include "net/proxy/proxy_server.h"
@@ -266,7 +266,8 @@ void ImportNetworksForUser(const user_manager::User* user,
 const base::DictionaryValue* FindPolicyForActiveUser(
     const std::string& guid,
     ::onc::ONCSource* onc_source) {
-  const user_manager::User* user = UserManager::Get()->GetActiveUser();
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->GetActiveUser();
   std::string username_hash = user ? user->username_hash() : std::string();
   return NetworkHandler::Get()->managed_network_configuration_handler()->
       FindPolicyByGUID(username_hash, guid, onc_source);
@@ -275,7 +276,8 @@ const base::DictionaryValue* FindPolicyForActiveUser(
 const base::DictionaryValue* GetGlobalConfigFromPolicy(bool for_active_user) {
   std::string username_hash;
   if (for_active_user) {
-    const user_manager::User* user = UserManager::Get()->GetActiveUser();
+    const user_manager::User* user =
+        user_manager::UserManager::Get()->GetActiveUser();
     if (!user) {
       LOG(ERROR) << "No user logged in yet.";
       return NULL;
diff --git a/chrome/browser/chromeos/ownership/owner_settings_service.cc b/chrome/browser/chromeos/ownership/owner_settings_service.cc
index b2581e2..a8fc0f2 100644
--- a/chrome/browser/chromeos/ownership/owner_settings_service.cc
+++ b/chrome/browser/chromeos/ownership/owner_settings_service.cc
@@ -9,14 +9,12 @@
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service_factory.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/settings/session_manager_operation.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "components/policy/core/common/cloud/cloud_policy_constants.h"
-#include "components/user_manager/user.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_service.h"
diff --git a/chrome/browser/chromeos/ownership/owner_settings_service_factory.cc b/chrome/browser/chromeos/ownership/owner_settings_service_factory.cc
index 9cf55d4..3154df4 100644
--- a/chrome/browser/chromeos/ownership/owner_settings_service_factory.cc
+++ b/chrome/browser/chromeos/ownership/owner_settings_service_factory.cc
@@ -4,12 +4,12 @@
 
 #include "chrome/browser/chromeos/ownership/owner_settings_service_factory.h"
 
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 
 namespace chromeos {
 
@@ -36,9 +36,10 @@ OwnerSettingsServiceFactory* OwnerSettingsServiceFactory::GetInstance() {
 
 void OwnerSettingsServiceFactory::SetUsername(const std::string& username) {
   username_ = username;
-  if (!UserManager::IsInitialized())
+  if (!user_manager::UserManager::IsInitialized())
     return;
-  const user_manager::User* user = UserManager::Get()->FindUser(username_);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(username_);
   if (!user || !user->is_profile_created())
     return;
   Profile* profile = ProfileHelper::Get()->GetProfileByUserUnsafe(user);
diff --git a/chrome/browser/chromeos/policy/blocking_login_browsertest.cc b/chrome/browser/chromeos/policy/blocking_login_browsertest.cc
index 54d4898..7cae921 100644
--- a/chrome/browser/chromeos/policy/blocking_login_browsertest.cc
+++ b/chrome/browser/chromeos/policy/blocking_login_browsertest.cc
@@ -13,7 +13,6 @@
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/existing_user_controller.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_display.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/enterprise_install_attributes.h"
@@ -23,6 +22,7 @@
 #include "chromeos/chromeos_switches.h"
 #include "components/policy/core/common/cloud/device_management_service.h"
 #include "components/policy/core/common/policy_switches.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/notification_service.h"
@@ -257,7 +257,7 @@ class BlockingLoginTest
 
 IN_PROC_BROWSER_TEST_P(BlockingLoginTest, LoginBlocksForUser) {
   // Verify that there isn't a logged in user when the test starts.
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   EXPECT_FALSE(user_manager->IsUserLoggedIn());
   EXPECT_FALSE(browser_policy_connector()->IsEnterpriseManaged());
   EXPECT_FALSE(profile_added_);
diff --git a/chrome/browser/chromeos/policy/device_local_account.h b/chrome/browser/chromeos/policy/device_local_account.h
index d10b228..175ab9c 100644
--- a/chrome/browser/chromeos/policy/device_local_account.h
+++ b/chrome/browser/chromeos/policy/device_local_account.h
@@ -43,7 +43,8 @@ struct DeviceLocalAccount {
   // The |account_id| is primarily used by policy code: If device policy defines
   // a device-local account with a certain |account_id|, the user policy for
   // that account has to be fetched by referencing the same |account_id|.
-  // The |user_id| is passed to the chromeos::UserManager where it becomes part
+  // The |user_id| is passed to the user_manager::UserManager where it becomes
+  // part
   // of the global user list on the device. The |account_id| would not be safe
   // to use here as it is a free-form identifier that could conflict with
   // another |user_id| on the device and cannot be easily identified as
diff --git a/chrome/browser/chromeos/policy/device_local_account_browsertest.cc b/chrome/browser/chromeos/policy/device_local_account_browsertest.cc
index 06ea719b..077d915a 100644
--- a/chrome/browser/chromeos/policy/device_local_account_browsertest.cc
+++ b/chrome/browser/chromeos/policy/device_local_account_browsertest.cc
@@ -51,8 +51,7 @@
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager_impl.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager_test_util.h"
-#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager_impl.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/cloud_external_data_manager_base_test_util.h"
@@ -104,6 +103,7 @@
 #include "components/policy/core/common/policy_switches.h"
 #include "components/signin/core/common/signin_pref_names.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_details.h"
@@ -374,7 +374,7 @@ scoped_ptr<net::FakeURLFetcher> RunCallbackAndReturnFakeURLFetcher(
 }
 
 bool IsSessionStarted() {
-  return chromeos::UserManager::Get()->IsSessionStarted();
+  return user_manager::UserManager::Get()->IsSessionStarted();
 }
 
 // GetKeyboardLayoutsForLocale() posts a task to a background task runner. This
@@ -397,7 +397,7 @@ void WaitForGetKeyboardLayoutsForLocaleToFinish() {
 }  // namespace
 
 class DeviceLocalAccountTest : public DevicePolicyCrosBrowserTest,
-                               public chromeos::UserManager::Observer,
+                               public user_manager::UserManager::Observer,
                                public chrome::BrowserListObserver,
                                public apps::AppWindowRegistry::Observer {
  protected:
@@ -519,7 +519,8 @@ class DeviceLocalAccountTest : public DevicePolicyCrosBrowserTest,
     base::RunLoop().RunUntilIdle();
   }
 
-  virtual void LocalStateChanged(chromeos::UserManager* user_manager) OVERRIDE {
+  virtual void LocalStateChanged(
+      user_manager::UserManager* user_manager) OVERRIDE {
     if (run_loop_)
       run_loop_->Quit();
   }
@@ -609,7 +610,8 @@ class DeviceLocalAccountTest : public DevicePolicyCrosBrowserTest,
   }
 
   void CheckPublicSessionPresent(const std::string& id) {
-    const user_manager::User* user = chromeos::UserManager::Get()->FindUser(id);
+    const user_manager::User* user =
+        user_manager::UserManager::Get()->FindUser(id);
     ASSERT_TRUE(user);
     EXPECT_EQ(id, user->email());
     EXPECT_EQ(user_manager::USER_TYPE_PUBLIC_ACCOUNT, user->GetType());
@@ -709,7 +711,7 @@ class DeviceLocalAccountTest : public DevicePolicyCrosBrowserTest,
 };
 
 static bool IsKnownUser(const std::string& account_id) {
-  return chromeos::UserManager::Get()->IsKnownUser(account_id);
+  return user_manager::UserManager::Get()->IsKnownUser(account_id);
 }
 
 IN_PROC_BROWSER_TEST_F(DeviceLocalAccountTest, LoginScreen) {
@@ -1065,13 +1067,13 @@ IN_PROC_BROWSER_TEST_F(DeviceLocalAccountTest, ExtensionsCached) {
 }
 
 IN_PROC_BROWSER_TEST_F(DeviceLocalAccountTest, ExternalData) {
-  // chromeos::UserManager requests an external data fetch whenever
+  // user_manager::UserManager requests an external data fetch whenever
   // the key::kUserAvatarImage policy is set. Since this test wants to
   // verify that the underlying policy subsystem will start a fetch
-  // without this request as well, the chromeos::UserManager must be
+  // without this request as well, the user_manager::UserManager must be
   // prevented from seeing the policy change.
-  reinterpret_cast<chromeos::ChromeUserManager*>(chromeos::UserManager::Get())
-      ->StopPolicyObserverForTesting();
+  reinterpret_cast<chromeos::ChromeUserManagerImpl*>(
+      user_manager::UserManager::Get())->StopPolicyObserverForTesting();
 
   UploadDeviceLocalAccountPolicy();
   AddPublicSessionToDevicePolicy(kAccountId1);
@@ -1194,17 +1196,17 @@ IN_PROC_BROWSER_TEST_F(DeviceLocalAccountTest, UserAvatarImage) {
   ASSERT_TRUE(broker);
 
   run_loop_.reset(new base::RunLoop);
-  chromeos::UserManager::Get()->AddObserver(this);
+  user_manager::UserManager::Get()->AddObserver(this);
   broker->core()->store()->Load();
   run_loop_->Run();
-  chromeos::UserManager::Get()->RemoveObserver(this);
+  user_manager::UserManager::Get()->RemoveObserver(this);
 
   scoped_ptr<gfx::ImageSkia> policy_image = chromeos::test::ImageLoader(
       test_dir.Append(chromeos::test::kUserAvatarImage1RelativePath)).Load();
   ASSERT_TRUE(policy_image);
 
   const user_manager::User* user =
-      chromeos::UserManager::Get()->FindUser(user_id_1_);
+      user_manager::UserManager::Get()->FindUser(user_id_1_);
   ASSERT_TRUE(user);
 
   base::FilePath user_data_dir;
diff --git a/chrome/browser/chromeos/policy/device_status_collector.cc b/chrome/browser/chromeos/policy/device_status_collector.cc
index c48eab4..377c827 100644
--- a/chrome/browser/chromeos/policy/device_status_collector.cc
+++ b/chrome/browser/chromeos/policy/device_status_collector.cc
@@ -17,7 +17,6 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/common/chrome_version_info.h"
@@ -28,6 +27,7 @@
 #include "chromeos/settings/cros_settings_names.h"
 #include "chromeos/system/statistics_provider.h"
 #include "components/policy/core/common/cloud/cloud_policy_constants.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/browser_thread.h"
 #include "policy/proto/device_management_backend.pb.h"
@@ -428,7 +428,7 @@ void DeviceStatusCollector::GetUsers(em::DeviceStatusReportRequest* request) {
   policy::BrowserPolicyConnectorChromeOS* connector =
       g_browser_process->platform_part()->browser_policy_connector_chromeos();
   const user_manager::UserList& users =
-      chromeos::UserManager::Get()->GetUsers();
+      user_manager::UserManager::Get()->GetUsers();
   user_manager::UserList::const_iterator user;
   for (user = users.begin(); user != users.end(); ++user) {
     // Only regular users are reported.
diff --git a/chrome/browser/chromeos/policy/device_status_collector_browsertest.cc b/chrome/browser/chromeos/policy/device_status_collector_browsertest.cc
index 6e4a1f5..215f6ec 100644
--- a/chrome/browser/chromeos/policy/device_status_collector_browsertest.cc
+++ b/chrome/browser/chromeos/policy/device_status_collector_browsertest.cc
@@ -13,7 +13,7 @@
 #include "base/run_loop.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/stub_enterprise_install_attributes.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
diff --git a/chrome/browser/chromeos/policy/policy_cert_service.cc b/chrome/browser/chromeos/policy/policy_cert_service.cc
index 53b61f9..ed503b5 100644
--- a/chrome/browser/chromeos/policy/policy_cert_service.cc
+++ b/chrome/browser/chromeos/policy/policy_cert_service.cc
@@ -7,9 +7,9 @@
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/logging.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/policy_cert_service_factory.h"
 #include "chrome/browser/chromeos/policy/policy_cert_verifier.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "net/cert/x509_certificate.h"
 
@@ -23,7 +23,7 @@ PolicyCertService::~PolicyCertService() {
 PolicyCertService::PolicyCertService(
     const std::string& user_id,
     UserNetworkConfigurationUpdater* net_conf_updater,
-    chromeos::UserManager* user_manager)
+    user_manager::UserManager* user_manager)
     : cert_verifier_(NULL),
       user_id_(user_id),
       net_conf_updater_(net_conf_updater),
@@ -36,13 +36,14 @@ PolicyCertService::PolicyCertService(
 
 PolicyCertService::PolicyCertService(const std::string& user_id,
                                      PolicyCertVerifier* verifier,
-                                     chromeos::UserManager* user_manager)
+                                     user_manager::UserManager* user_manager)
     : cert_verifier_(verifier),
       user_id_(user_id),
       net_conf_updater_(NULL),
       user_manager_(user_manager),
       has_trust_anchors_(false),
-      weak_ptr_factory_(this) {}
+      weak_ptr_factory_(this) {
+}
 
 scoped_ptr<PolicyCertVerifier> PolicyCertService::CreatePolicyCertVerifier() {
   base::Closure callback = base::Bind(
@@ -109,7 +110,7 @@ void PolicyCertService::Shutdown() {
 scoped_ptr<PolicyCertService> PolicyCertService::CreateForTesting(
     const std::string& user_id,
     PolicyCertVerifier* verifier,
-    chromeos::UserManager* user_manager) {
+    user_manager::UserManager* user_manager) {
   return make_scoped_ptr(
       new PolicyCertService(user_id, verifier, user_manager));
 }
diff --git a/chrome/browser/chromeos/policy/policy_cert_service.h b/chrome/browser/chromeos/policy/policy_cert_service.h
index c514ba1..e32ca25 100644
--- a/chrome/browser/chromeos/policy/policy_cert_service.h
+++ b/chrome/browser/chromeos/policy/policy_cert_service.h
@@ -16,7 +16,7 @@
 #include "chrome/browser/chromeos/policy/user_network_configuration_updater.h"
 #include "components/keyed_service/core/keyed_service.h"
 
-namespace chromeos {
+namespace user_manager {
 class UserManager;
 }
 
@@ -40,7 +40,7 @@ class PolicyCertService
  public:
   PolicyCertService(const std::string& user_id,
                     UserNetworkConfigurationUpdater* net_conf_updater,
-                    chromeos::UserManager* user_manager);
+                    user_manager::UserManager* user_manager);
   virtual ~PolicyCertService();
 
   // Creates an associated PolicyCertVerifier. The returned object must only be
@@ -64,17 +64,17 @@ class PolicyCertService
   static scoped_ptr<PolicyCertService> CreateForTesting(
       const std::string& user_id,
       PolicyCertVerifier* verifier,
-      chromeos::UserManager* user_manager);
+      user_manager::UserManager* user_manager);
 
  private:
   PolicyCertService(const std::string& user_id,
                     PolicyCertVerifier* verifier,
-                    chromeos::UserManager* user_manager);
+                    user_manager::UserManager* user_manager);
 
   PolicyCertVerifier* cert_verifier_;
   std::string user_id_;
   UserNetworkConfigurationUpdater* net_conf_updater_;
-  chromeos::UserManager* user_manager_;
+  user_manager::UserManager* user_manager_;
   bool has_trust_anchors_;
 
   // Weak pointers to handle callbacks from PolicyCertVerifier on the IO thread.
diff --git a/chrome/browser/chromeos/policy/policy_cert_service_factory.cc b/chrome/browser/chromeos/policy/policy_cert_service_factory.cc
index a8c8ef0..b0bee1c 100644
--- a/chrome/browser/chromeos/policy/policy_cert_service_factory.cc
+++ b/chrome/browser/chromeos/policy/policy_cert_service_factory.cc
@@ -9,7 +9,6 @@
 #include "base/prefs/pref_service.h"
 #include "base/prefs/scoped_user_pref_update.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/policy_cert_service.h"
 #include "chrome/browser/chromeos/policy/policy_cert_verifier.h"
 #include "chrome/browser/chromeos/policy/user_network_configuration_updater_factory.h"
@@ -20,6 +19,7 @@
 #include "chrome/common/pref_names.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "components/pref_registry/pref_registry_syncable.h"
+#include "components/user_manager/user_manager.h"
 
 namespace policy {
 
@@ -94,7 +94,7 @@ KeyedService* PolicyCertServiceFactory::BuildServiceInstanceFor(
     content::BrowserContext* context) const {
   Profile* profile = static_cast<Profile*>(context);
 
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   user_manager::User* user = chromeos::ProfileHelper::Get()->GetUserByProfile(
       profile->GetOriginalProfile());
   if (!user)
diff --git a/chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos.cc b/chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos.cc
index f7c8d54..1dc5111 100644
--- a/chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos.cc
+++ b/chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos.cc
@@ -25,6 +25,7 @@
 #include "components/policy/core/common/policy_map.h"
 #include "components/policy/core/common/policy_pref_names.h"
 #include "components/policy/core/common/policy_types.h"
+#include "components/user_manager/user_manager.h"
 #include "net/url_request/url_request_context_getter.h"
 #include "policy/policy_constants.h"
 #include "url/gurl.h"
@@ -63,7 +64,7 @@ void OnWildcardCheckCompleted(const std::string& username,
     // logged-in session is not possible. Fix this either by delaying the
     // cryptohome deletion operation or by getting rid of the in-session
     // wildcard check.
-    chromeos::UserManager::Get()->RemoveUserFromList(username);
+    user_manager::UserManager::Get()->RemoveUserFromList(username);
     chrome::AttemptUserExit();
   }
 }
diff --git a/chrome/browser/chromeos/policy/user_cloud_policy_manager_factory_chromeos.cc b/chrome/browser/chromeos/policy/user_cloud_policy_manager_factory_chromeos.cc
index 5eb1590..e7a14dc 100644
--- a/chrome/browser/chromeos/policy/user_cloud_policy_manager_factory_chromeos.cc
+++ b/chrome/browser/chromeos/policy/user_cloud_policy_manager_factory_chromeos.cc
@@ -16,7 +16,6 @@
 #include "base/time/time.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/login/login_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/user_cloud_external_data_manager.h"
 #include "chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos.h"
@@ -33,6 +32,7 @@
 #include "components/policy/core/common/cloud/cloud_external_data_manager.h"
 #include "components/policy/core/common/cloud/device_management_service.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/browser_thread.h"
 #include "net/url_request/url_request_context_getter.h"
@@ -150,10 +150,11 @@ scoped_ptr<UserCloudPolicyManagerChromeOS>
       command_line->HasSwitch(chromeos::switches::kLoginUser);
   const bool wait_for_initial_policy =
       !is_browser_restart &&
-      (chromeos::UserManager::Get()->IsCurrentUserNew() || is_affiliated_user);
+      (user_manager::UserManager::Get()->IsCurrentUserNew() ||
+       is_affiliated_user);
 
   const base::TimeDelta initial_policy_fetch_timeout =
-      chromeos::UserManager::Get()->IsCurrentUserNew()
+      user_manager::UserManager::Get()->IsCurrentUserNew()
           ? base::TimeDelta::Max()
           : base::TimeDelta::FromSeconds(kInitialPolicyFetchTimeoutSeconds);
 
diff --git a/chrome/browser/chromeos/policy/user_network_configuration_updater_factory.cc b/chrome/browser/chromeos/policy/user_network_configuration_updater_factory.cc
index f332147..5d22dc7 100644
--- a/chrome/browser/chromeos/policy/user_network_configuration_updater_factory.cc
+++ b/chrome/browser/chromeos/policy/user_network_configuration_updater_factory.cc
@@ -5,7 +5,6 @@
 #include "chrome/browser/chromeos/policy/user_network_configuration_updater_factory.h"
 
 #include "base/memory/singleton.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/user_network_configuration_updater.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/policy/profile_policy_connector.h"
@@ -17,6 +16,7 @@
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "components/policy/core/common/cloud/cloud_policy_constants.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 
 namespace policy {
@@ -71,7 +71,7 @@ KeyedService* UserNetworkConfigurationUpdaterFactory::BuildServiceInstanceFor(
   DCHECK(user);
   // Currently, only the network policy of the primary user is supported. See
   // also http://crbug.com/310685 .
-  if (user != chromeos::UserManager::Get()->GetPrimaryUser())
+  if (user != user_manager::UserManager::Get()->GetPrimaryUser())
     return NULL;
 
   const bool allow_trusted_certs_from_policy =
diff --git a/chrome/browser/chromeos/preferences.cc b/chrome/browser/chromeos/preferences.cc
index f649254..60f7bae 100644
--- a/chrome/browser/chromeos/preferences.cc
+++ b/chrome/browser/chromeos/preferences.cc
@@ -71,7 +71,7 @@ Preferences::Preferences(input_method::InputMethodManager* input_method_manager)
 
 Preferences::~Preferences() {
   prefs_->RemoveObserver(this);
-  UserManager::Get()->RemoveSessionStateObserver(this);
+  user_manager::UserManager::Get()->RemoveSessionStateObserver(this);
   // If shell instance is destoryed before this preferences instance, there is
   // no need to remove this shell observer.
   if (ash::Shell::HasInstance())
@@ -353,10 +353,11 @@ void Preferences::Init(PrefServiceSyncable* prefs,
                        const user_manager::User* user) {
   DCHECK(user);
   user_ = user;
-  user_is_primary_ = UserManager::Get()->GetPrimaryUser() == user_;
+  user_is_primary_ =
+      user_manager::UserManager::Get()->GetPrimaryUser() == user_;
   InitUserPrefs(prefs);
 
-  UserManager::Get()->AddSessionStateObserver(this);
+  user_manager::UserManager::Get()->AddSessionStateObserver(this);
 
   // This causes OnIsSyncingChanged to be called when the value of
   // PrefService::IsSyncing() changes.
@@ -390,7 +391,7 @@ void Preferences::ApplyPreferences(ApplyReason reason,
                                    const std::string& pref_name) {
   DCHECK(reason != REASON_PREF_CHANGED || !pref_name.empty());
   const bool user_is_owner =
-      UserManager::Get()->GetOwnerEmail() == user_->email();
+      user_manager::UserManager::Get()->GetOwnerEmail() == user_->email();
   const bool user_is_active = user_->is_active();
 
   system::TouchpadSettings touchpad_settings;
diff --git a/chrome/browser/chromeos/preferences.h b/chrome/browser/chromeos/preferences.h
index bf8e6e6..0d24b05 100644
--- a/chrome/browser/chromeos/preferences.h
+++ b/chrome/browser/chromeos/preferences.h
@@ -12,8 +12,8 @@
 #include "base/compiler_specific.h"
 #include "base/prefs/pref_member.h"
 #include "chrome/browser/chromeos/language_preferences.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/prefs/pref_service_syncable_observer.h"
+#include "components/user_manager/user_manager.h"
 
 class PrefRegistrySimple;
 class PrefService;
@@ -39,7 +39,7 @@ class InputMethodManager;
 // When the preferences change, we change the settings to reflect the new value.
 class Preferences : public PrefServiceSyncableObserver,
                     public ash::ShellObserver,
-                    public UserManager::UserSessionStateObserver {
+                    public user_manager::UserManager::UserSessionStateObserver {
  public:
   Preferences();
   explicit Preferences(
@@ -103,7 +103,7 @@ class Preferences : public PrefServiceSyncableObserver,
   // Overriden from ash::ShellObserver.
   virtual void OnTouchHudProjectionToggled(bool enabled) OVERRIDE;
 
-  // Overriden form UserManager::UserSessionStateObserver.
+  // Overriden form user_manager::UserManager::UserSessionStateObserver.
   virtual void ActiveUserChanged(
       const user_manager::User* active_user) OVERRIDE;
 
diff --git a/chrome/browser/chromeos/preferences_browsertest.cc b/chrome/browser/chromeos/preferences_browsertest.cc
index 9c6f1da..d28efed 100644
--- a/chrome/browser/chromeos/preferences_browsertest.cc
+++ b/chrome/browser/chromeos/preferences_browsertest.cc
@@ -13,7 +13,6 @@
 #include "chrome/browser/chromeos/login/login_manager_test.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/preferences.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
@@ -24,6 +23,7 @@
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/ime/fake_ime_keyboard.h"
 #include "components/feedback/tracing_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/test/test_utils.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/events/event_utils.h"
@@ -139,7 +139,7 @@ IN_PROC_BROWSER_TEST_F(PreferencesTest, PRE_MultiProfiles) {
 }
 
 IN_PROC_BROWSER_TEST_F(PreferencesTest, MultiProfiles) {
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
   // Add first user and init its preferences. Check that corresponding
   // settings has been changed.
diff --git a/chrome/browser/chromeos/preferences_unittest.cc b/chrome/browser/chromeos/preferences_unittest.cc
index 0f444d0..62cc543 100644
--- a/chrome/browser/chromeos/preferences_unittest.cc
+++ b/chrome/browser/chromeos/preferences_unittest.cc
@@ -7,7 +7,7 @@
 #include "base/prefs/pref_member.h"
 #include "chrome/browser/chromeos/input_method/mock_input_method_manager.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/download/download_prefs.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_pref_service_syncable.h"
diff --git a/chrome/browser/chromeos/profiles/avatar_menu_actions_chromeos.cc b/chrome/browser/chromeos/profiles/avatar_menu_actions_chromeos.cc
index c88c50b..a65eae2 100644
--- a/chrome/browser/chromeos/profiles/avatar_menu_actions_chromeos.cc
+++ b/chrome/browser/chromeos/profiles/avatar_menu_actions_chromeos.cc
@@ -7,9 +7,10 @@
 #include "ash/multi_profile_uma.h"
 #include "ash/shell.h"
 #include "ash/system/tray/system_tray_delegate.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_avatar_icon_util.h"
 #include "chrome/browser/ui/browser.h"
+#include "components/user_manager/user_manager.h"
 
 // static
 AvatarMenuActions* AvatarMenuActions::Create() {
@@ -38,7 +39,9 @@ void AvatarMenuActionsChromeOS::EditProfile(Profile* profile, size_t index) {
 bool AvatarMenuActionsChromeOS::ShouldShowAddNewProfileLink() const {
   // |browser_| can be NULL in unit_tests.
   return (!browser_ || !browser_->profile()->IsSupervised()) &&
-      UserManager::Get()->GetUsersAdmittedForMultiProfile().size();
+         user_manager::UserManager::Get()
+             ->GetUsersAdmittedForMultiProfile()
+             .size();
 }
 
 bool AvatarMenuActionsChromeOS::ShouldShowEditProfileLink() const {
diff --git a/chrome/browser/chromeos/profiles/profile_helper.cc b/chrome/browser/chromeos/profiles/profile_helper.cc
index f960630..fc95ed6 100644
--- a/chrome/browser/chromeos/profiles/profile_helper.cc
+++ b/chrome/browser/chromeos/profiles/profile_helper.cc
@@ -9,7 +9,6 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browsing_data/browsing_data_helper.h"
 #include "chrome/browser/chromeos/login/signin/oauth2_login_manager_factory.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/profiles/profiles_state.h"
@@ -17,6 +16,7 @@
 #include "chrome/common/chrome_switches.h"
 #include "chromeos/chromeos_switches.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace chromeos {
@@ -61,8 +61,8 @@ ProfileHelper::ProfileHelper()
 ProfileHelper::~ProfileHelper() {
   // Checking whether UserManager is initialized covers case
   // when ScopedTestUserManager is used.
-  if (UserManager::IsInitialized())
-    UserManager::Get()->RemoveSessionStateObserver(this);
+  if (user_manager::UserManager::IsInitialized())
+    user_manager::UserManager::Get()->RemoveSessionStateObserver(this);
 }
 
 // static
@@ -151,7 +151,8 @@ base::FilePath ProfileHelper::GetUserProfileDirByUserId(
   // ProfileManager and use only this function to construct profile path.
   // TODO(nkostylev): Cleanup profile dir related code paths crbug.com/294233
   base::FilePath profile_dir;
-  const user_manager::User* user = UserManager::Get()->FindUser(user_id);
+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(user_id);
   if (user && !user->username_hash().empty())
     profile_dir = ProfileHelper::GetUserProfileDir(user->username_hash());
 
@@ -174,7 +175,7 @@ bool ProfileHelper::IsOwnerProfile(Profile* profile) {
   if (!user)
     return false;
 
-  return user->email() == chromeos::UserManager::Get()->GetOwnerEmail();
+  return user->email() == user_manager::UserManager::Get()->GetOwnerEmail();
 }
 
 // static
@@ -184,7 +185,7 @@ bool ProfileHelper::IsPrimaryProfile(Profile* profile) {
   user_manager::User* user = ProfileHelper::Get()->GetUserByProfile(profile);
   if (!user)
     return false;
-  return user == chromeos::UserManager::Get()->GetPrimaryUser();
+  return user == user_manager::UserManager::Get()->GetPrimaryUser();
 }
 
 void ProfileHelper::ProfileStartup(Profile* profile, bool process_startup) {
@@ -198,8 +199,8 @@ void ProfileHelper::ProfileStartup(Profile* profile, bool process_startup) {
   // Add observer so we can see when the first profile's session restore is
   // completed. After that, we won't need the default profile anymore.
   if (!IsSigninProfile(profile) &&
-      UserManager::Get()->IsLoggedInAsRegularUser() &&
-      !UserManager::Get()->IsLoggedInAsStub()) {
+      user_manager::UserManager::Get()->IsLoggedInAsRegularUser() &&
+      !user_manager::UserManager::Get()->IsLoggedInAsStub()) {
     chromeos::OAuth2LoginManager* login_manager =
         chromeos::OAuth2LoginManagerFactory::GetInstance()->GetForProfile(
             profile);
@@ -213,7 +214,7 @@ base::FilePath ProfileHelper::GetActiveUserProfileDir() {
 }
 
 void ProfileHelper::Initialize() {
-  UserManager::Get()->AddSessionStateObserver(this);
+  user_manager::UserManager::Get()->AddSessionStateObserver(this);
 }
 
 void ProfileHelper::ClearSigninProfile(const base::Closure& on_clear_callback) {
@@ -249,7 +250,7 @@ Profile* ProfileHelper::GetProfileByUser(const user_manager::User* user) {
 
   // GetActiveUserProfile() or GetProfileByUserIdHash() returns a new instance
   // of ProfileImpl(), but actually its OffTheRecordProfile() should be used.
-  if (UserManager::Get()->IsLoggedInAsGuest())
+  if (user_manager::UserManager::Get()->IsLoggedInAsGuest())
     profile = profile->GetOffTheRecordProfile();
 
   return profile;
@@ -276,7 +277,7 @@ Profile* ProfileHelper::GetProfileByUserUnsafe(const user_manager::User* user) {
 
   // GetActiveUserProfile() or GetProfileByUserIdHash() returns a new instance
   // of ProfileImpl(), but actually its OffTheRecordProfile() should be used.
-  if (profile && UserManager::Get()->IsLoggedInAsGuest())
+  if (profile && user_manager::UserManager::Get()->IsLoggedInAsGuest())
     profile = profile->GetOffTheRecordProfile();
   return profile;
 }
@@ -286,7 +287,7 @@ user_manager::User* ProfileHelper::GetUserByProfile(Profile* profile) {
   if (enable_profile_to_user_testing || !user_list_for_testing_.empty()) {
     if (always_return_primary_user_for_testing)
       return const_cast<user_manager::User*>(
-          UserManager::Get()->GetPrimaryUser());
+          user_manager::UserManager::Get()->GetPrimaryUser());
 
     const std::string& user_name = profile->GetProfileName();
     for (user_manager::UserList::const_iterator it =
@@ -299,14 +300,14 @@ user_manager::User* ProfileHelper::GetUserByProfile(Profile* profile) {
 
     // In case of test setup we should always default to primary user.
     return const_cast<user_manager::User*>(
-        UserManager::Get()->GetPrimaryUser());
+        user_manager::UserManager::Get()->GetPrimaryUser());
   }
 
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
   if (ProfileHelper::IsSigninProfile(profile))
     return NULL;
 
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
   // Special case for non-CrOS tests that do create several profiles
   // and don't really care about mapping to the real user.
diff --git a/chrome/browser/chromeos/profiles/profile_helper.h b/chrome/browser/chromeos/profiles/profile_helper.h
index 04afba4..3dd899e 100644
--- a/chrome/browser/chromeos/profiles/profile_helper.h
+++ b/chrome/browser/chromeos/profiles/profile_helper.h
@@ -13,7 +13,7 @@
 #include "base/files/file_path.h"
 #include "chrome/browser/browsing_data/browsing_data_remover.h"
 #include "chrome/browser/chromeos/login/signin/oauth2_login_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 
 class Profile;
 class User;
@@ -39,9 +39,10 @@ namespace chromeos {
 // 2. Get profile dir of an active user, used by ProfileManager:
 //    GetActiveUserProfileDir()
 // 3. Get mapping from user_id_hash to Profile instance/profile path etc.
-class ProfileHelper : public BrowsingDataRemover::Observer,
-                      public OAuth2LoginManager::Observer,
-                      public UserManager::UserSessionStateObserver {
+class ProfileHelper
+    : public BrowsingDataRemover::Observer,
+      public OAuth2LoginManager::Observer,
+      public user_manager::UserManager::UserSessionStateObserver {
  public:
   ProfileHelper();
   virtual ~ProfileHelper();
@@ -139,12 +140,12 @@ class ProfileHelper : public BrowsingDataRemover::Observer,
   // BrowsingDataRemover::Observer implementation:
   virtual void OnBrowsingDataRemoverDone() OVERRIDE;
 
-  // UserManager::Observer overrides.
+  // OAuth2LoginManager::Observer overrides.
   virtual void OnSessionRestoreStateChanged(
       Profile* user_profile,
       OAuth2LoginManager::SessionRestoreState state) OVERRIDE;
 
-  // UserManager::UserSessionStateObserver implementation:
+  // user_manager::UserManager::UserSessionStateObserver implementation:
   virtual void ActiveUserHashChanged(const std::string& hash) OVERRIDE;
 
   // Associates |user| with profile with the same user_id,
diff --git a/chrome/browser/chromeos/profiles/profile_list_chromeos.cc b/chrome/browser/chromeos/profiles/profile_list_chromeos.cc
index b49bcac..d8f7591 100644
--- a/chrome/browser/chromeos/profiles/profile_list_chromeos.cc
+++ b/chrome/browser/chromeos/profiles/profile_list_chromeos.cc
@@ -8,12 +8,12 @@
 
 #include "ash/shell.h"
 #include "base/command_line.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile_avatar_icon_util.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/chrome_switches.h"
 #include "components/signin/core/common/profile_management_switches.h"
+#include "components/user_manager/user_manager.h"
 
 // static
 ProfileList* ProfileList::Create(ProfileInfoInterface* profile_cache) {
@@ -43,7 +43,8 @@ void ProfileListChromeOS::RebuildMenu() {
   ClearMenu();
 
   // Filter for profiles associated with logged-in users.
-  user_manager::UserList users = UserManager::Get()->GetLoggedInUsers();
+  user_manager::UserList users =
+      user_manager::UserManager::Get()->GetLoggedInUsers();
 
   // Add corresponding profiles.
   for (user_manager::UserList::const_iterator it = users.begin();
diff --git a/chrome/browser/chromeos/profiles/profile_list_chromeos_unittest.cc b/chrome/browser/chromeos/profiles/profile_list_chromeos_unittest.cc
index 6f47d2e..398aa3e 100644
--- a/chrome/browser/chromeos/profiles/profile_list_chromeos_unittest.cc
+++ b/chrome/browser/chromeos/profiles/profile_list_chromeos_unittest.cc
@@ -10,6 +10,7 @@
 #include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/prefs/pref_service_syncable.h"
 #include "chrome/browser/profiles/avatar_menu.h"
@@ -69,7 +70,7 @@ class ProfileListChromeOSTest : public testing::Test {
   }
 
   FakeUserManager* GetFakeUserManager() {
-    return static_cast<FakeUserManager*>(UserManager::Get());
+    return static_cast<FakeUserManager*>(user_manager::UserManager::Get());
   }
 
   void AddProfile(base::string16 name, bool log_in) {
diff --git a/chrome/browser/chromeos/proxy_config_service_impl.cc b/chrome/browser/chromeos/proxy_config_service_impl.cc
index 89d07f6..9134736 100644
--- a/chrome/browser/chromeos/proxy_config_service_impl.cc
+++ b/chrome/browser/chromeos/proxy_config_service_impl.cc
@@ -12,7 +12,6 @@
 #include "base/prefs/pref_service.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/net/proxy_config_handler.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/prefs/proxy_config_dictionary.h"
@@ -24,6 +23,7 @@
 #include "chromeos/network/network_state_handler.h"
 #include "chromeos/network/onc/onc_utils.h"
 #include "components/policy/core/common/cloud/cloud_policy_constants.h"
+#include "components/user_manager/user_manager.h"
 
 namespace chromeos {
 
@@ -144,7 +144,7 @@ bool ProxyConfigServiceImpl::IgnoreProxy(const PrefService* profile_prefs,
     policy::BrowserPolicyConnectorChromeOS* connector =
         g_browser_process->platform_part()->browser_policy_connector_chromeos();
     const user_manager::User* logged_in_user =
-        UserManager::Get()->GetLoggedInUser();
+        user_manager::UserManager::Get()->GetLoggedInUser();
     if (connector->GetUserAffiliation(logged_in_user->email()) ==
         policy::USER_AFFILIATION_MANAGED) {
       VLOG(1) << "Respecting proxy for network, as logged-in user belongs to "
diff --git a/chrome/browser/chromeos/settings/device_settings_test_helper.h b/chrome/browser/chromeos/settings/device_settings_test_helper.h
index 8ac6a00..fc66da9 100644
--- a/chrome/browser/chromeos/settings/device_settings_test_helper.h
+++ b/chrome/browser/chromeos/settings/device_settings_test_helper.h
@@ -16,7 +16,7 @@
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_util.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/policy/device_policy_builder.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #include "chrome/browser/chromeos/settings/device_settings_test_helper.h"
diff --git a/chrome/browser/chromeos/settings/session_manager_operation.cc b/chrome/browser/chromeos/settings/session_manager_operation.cc
index 44aadfe..37b9626 100644
--- a/chrome/browser/chromeos/settings/session_manager_operation.cc
+++ b/chrome/browser/chromeos/settings/session_manager_operation.cc
@@ -11,12 +11,10 @@
 #include "base/stl_util.h"
 #include "base/task_runner_util.h"
 #include "base/threading/sequenced_worker_pool.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/proto/chrome_device_policy.pb.h"
 #include "chrome/browser/chromeos/settings/owner_key_util.h"
 #include "chrome/browser/net/nss_context.h"
 #include "components/policy/core/common/cloud/cloud_policy_constants.h"
-#include "components/user_manager/user.h"
 #include "content/public/browser/browser_thread.h"
 #include "crypto/rsa_private_key.h"
 #include "crypto/signature_creator.h"
diff --git a/chrome/browser/chromeos/settings/stub_cros_settings_provider.cc b/chrome/browser/chromeos/settings/stub_cros_settings_provider.cc
index 0202da7..c11e3c3 100644
--- a/chrome/browser/chromeos/settings/stub_cros_settings_provider.cc
+++ b/chrome/browser/chromeos/settings/stub_cros_settings_provider.cc
@@ -6,7 +6,6 @@
 
 #include "base/logging.h"
 #include "base/values.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_provider.h"
 #include "chromeos/settings/cros_settings_names.h"
diff --git a/chrome/browser/chromeos/sim_dialog_delegate.cc b/chrome/browser/chromeos/sim_dialog_delegate.cc
index ebb819f..7e49665 100644
--- a/chrome/browser/chromeos/sim_dialog_delegate.cc
+++ b/chrome/browser/chromeos/sim_dialog_delegate.cc
@@ -5,7 +5,6 @@
 #include "chrome/browser/chromeos/sim_dialog_delegate.h"
 
 #include "base/strings/stringprintf.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/ui/browser_dialogs.h"
 #include "chrome/common/url_constants.h"
diff --git a/chrome/browser/chromeos/status/network_menu.cc b/chrome/browser/chromeos/status/network_menu.cc
index 07dcba04..4efcc07 100644
--- a/chrome/browser/chromeos/status/network_menu.cc
+++ b/chrome/browser/chromeos/status/network_menu.cc
@@ -15,7 +15,6 @@
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/mobile_config.h"
 #include "chrome/browser/chromeos/options/network_config_view.h"
 #include "chrome/browser/chromeos/sim_dialog_delegate.h"
diff --git a/chrome/browser/chromeos/system/automatic_reboot_manager.cc b/chrome/browser/chromeos/system/automatic_reboot_manager.cc
index b5370b7..6e96e41 100644
--- a/chrome/browser/chromeos/system/automatic_reboot_manager.cc
+++ b/chrome/browser/chromeos/system/automatic_reboot_manager.cc
@@ -33,12 +33,12 @@
 #include "base/time/tick_clock.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/system/automatic_reboot_manager_observer.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/chromeos_paths.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_service.h"
@@ -171,7 +171,7 @@ AutomaticRebootManager::AutomaticRebootManager(
   // If no user is logged in, a reboot may be performed whenever the user is
   // idle. Start listening for user activity to determine whether the user is
   // idle or not.
-  if (!UserManager::Get()->IsUserLoggedIn()) {
+  if (!user_manager::UserManager::Get()->IsUserLoggedIn()) {
     if (ash::Shell::HasInstance())
       ash::Shell::GetInstance()->user_activity_detector()->AddObserver(this);
     notification_registrar_.Add(this, chrome::NOTIFICATION_LOGIN_USER_CHANGED,
@@ -262,7 +262,7 @@ void AutomaticRebootManager::Observe(
     const content::NotificationSource& source,
     const content::NotificationDetails& details) {
   if (type == chrome::NOTIFICATION_APP_TERMINATING) {
-    if (UserManager::Get()->IsUserLoggedIn()) {
+    if (user_manager::UserManager::Get()->IsUserLoggedIn()) {
       // The browser is terminating during a session, either because the session
       // is ending or because the browser is being restarted.
       MaybeReboot(true);
@@ -395,7 +395,7 @@ void AutomaticRebootManager::MaybeReboot(bool ignore_session) {
   // * A session is in progress and |ignore_session| is not set.
   if (!reboot_requested_ ||
       (login_screen_idle_timer_ && login_screen_idle_timer_->IsRunning()) ||
-      (!ignore_session && UserManager::Get()->IsUserLoggedIn())) {
+      (!ignore_session && user_manager::UserManager::Get()->IsUserLoggedIn())) {
     return;
   }
 
@@ -404,8 +404,8 @@ void AutomaticRebootManager::MaybeReboot(bool ignore_session) {
 
 void AutomaticRebootManager::Reboot() {
   // If a non-kiosk-app session is in progress, do not reboot.
-  if (UserManager::Get()->IsUserLoggedIn() &&
-      !UserManager::Get()->IsLoggedInAsKioskApp()) {
+  if (user_manager::UserManager::Get()->IsUserLoggedIn() &&
+      !user_manager::UserManager::Get()->IsLoggedInAsKioskApp()) {
     return;
   }
 
diff --git a/chrome/browser/chromeos/system/automatic_reboot_manager_unittest.cc b/chrome/browser/chromeos/system/automatic_reboot_manager_unittest.cc
index 70c431e..32310a2 100644
--- a/chrome/browser/chromeos/system/automatic_reboot_manager_unittest.cc
+++ b/chrome/browser/chromeos/system/automatic_reboot_manager_unittest.cc
@@ -28,7 +28,7 @@
 #include "base/values.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_browser_process.h"
 #include "chromeos/chromeos_paths.h"
diff --git a/chrome/browser/chromeos/system/tray_accessibility_browsertest.cc b/chrome/browser/chromeos/system/tray_accessibility_browsertest.cc
index c84338b..b097f4f 100644
--- a/chrome/browser/chromeos/system/tray_accessibility_browsertest.cc
+++ b/chrome/browser/chromeos/system/tray_accessibility_browsertest.cc
@@ -20,7 +20,6 @@
 #include "chrome/browser/chromeos/login/helper.h"
 #include "chrome/browser/chromeos/login/login_utils.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/extensions/api/braille_display_private/mock_braille_controller.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
@@ -34,6 +33,7 @@
 #include "components/policy/core/common/mock_configuration_policy_provider.h"
 #include "components/policy/core/common/policy_map.h"
 #include "components/policy/core/common/policy_types.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/test/test_utils.h"
 #include "policy/policy_constants.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -271,9 +271,9 @@ class TrayAccessibilityTest
 IN_PROC_BROWSER_TEST_P(TrayAccessibilityTest, LoginStatus) {
   EXPECT_EQ(ash::user::LOGGED_IN_NONE, GetLoginStatus());
 
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       "owner@invalid.domain", "owner@invalid.domain", true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   EXPECT_EQ(ash::user::LOGGED_IN_USER, GetLoginStatus());
 }
@@ -285,9 +285,9 @@ IN_PROC_BROWSER_TEST_P(TrayAccessibilityTest, DISABLED_ShowTrayIcon) {
   // Confirms that the icon is invisible before login.
   EXPECT_FALSE(IsTrayIconVisible());
 
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       "owner@invalid.domain", "owner@invalid.domain", true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   // Confirms that the icon is invisible just after login.
   EXPECT_FALSE(IsTrayIconVisible());
@@ -351,9 +351,9 @@ IN_PROC_BROWSER_TEST_P(TrayAccessibilityTest, DISABLED_ShowTrayIcon) {
 // http://crbug.com/396342
 IN_PROC_BROWSER_TEST_P(TrayAccessibilityTest, DISABLED_ShowMenu) {
   // Login
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       "owner@invalid.domain", "owner@invalid.domain", true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   SetShowAccessibilityOptionsInSystemTrayMenu(false);
 
@@ -421,9 +421,9 @@ IN_PROC_BROWSER_TEST_P(TrayAccessibilityTest, DISABLED_ShowMenu) {
 IN_PROC_BROWSER_TEST_P(TrayAccessibilityTest,
     DISABLED_ShowMenuWithShowMenuOption) {
   // Login
-  UserManager::Get()->UserLoggedIn(
+  user_manager::UserManager::Get()->UserLoggedIn(
       "owner@invalid.domain", "owner@invalid.domain", true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   SetShowAccessibilityOptionsInSystemTrayMenu(true);
 
diff --git a/chrome/browser/chromeos/system_logs/debug_daemon_log_source.cc b/chrome/browser/chromeos/system_logs/debug_daemon_log_source.cc
index d5327d6..fa3c395 100644
--- a/chrome/browser/chromeos/system_logs/debug_daemon_log_source.cc
+++ b/chrome/browser/chromeos/system_logs/debug_daemon_log_source.cc
@@ -12,11 +12,11 @@
 #include "base/memory/weak_ptr.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/chrome_switches.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/debug_daemon_client.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 
 const char kNotAvailable[] = "<not available>";
@@ -136,9 +136,8 @@ void DebugDaemonLogSource::OnGetUserLogFiles(
     SystemLogsResponse* response = new SystemLogsResponse;
     std::vector<Profile*> last_used = ProfileManager::GetLastOpenedProfiles();
 
-    if (last_used.empty() &&
-        chromeos::UserManager::IsInitialized() &&
-        chromeos::UserManager::Get()->IsLoggedInAsKioskApp()) {
+    if (last_used.empty() && user_manager::UserManager::IsInitialized() &&
+        user_manager::UserManager::Get()->IsLoggedInAsKioskApp()) {
       // Use the kiosk app profile explicitly because kiosk session does not
       // open any browsers thus ProfileManager::GetLastOpenedProfiles returns
       // an empty |last_used|.
diff --git a/chrome/browser/chromeos/ui/choose_mobile_network_dialog.cc b/chrome/browser/chromeos/ui/choose_mobile_network_dialog.cc
index 11ce289..ad5acc3 100644
--- a/chrome/browser/chromeos/ui/choose_mobile_network_dialog.cc
+++ b/chrome/browser/chromeos/ui/choose_mobile_network_dialog.cc
@@ -4,7 +4,6 @@
 
 #include "chrome/browser/chromeos/ui/choose_mobile_network_dialog.h"
 
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/ui/browser_dialogs.h"
 #include "chrome/common/url_constants.h"
diff --git a/chrome/browser/extensions/activity_log/activity_database_unittest.cc b/chrome/browser/extensions/activity_log/activity_database_unittest.cc
index 7b1e135..1ad7121 100644
--- a/chrome/browser/extensions/activity_log/activity_database_unittest.cc
+++ b/chrome/browser/extensions/activity_log/activity_database_unittest.cc
@@ -28,7 +28,7 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #include "chromeos/chromeos_switches.h"
diff --git a/chrome/browser/extensions/activity_log/activity_log_enabled_unittest.cc b/chrome/browser/extensions/activity_log/activity_log_enabled_unittest.cc
index 4f516bb..ff831014 100644
--- a/chrome/browser/extensions/activity_log/activity_log_enabled_unittest.cc
+++ b/chrome/browser/extensions/activity_log/activity_log_enabled_unittest.cc
@@ -17,7 +17,7 @@
 #include "extensions/common/extension_builder.h"
 
 #if defined OS_CHROMEOS
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/activity_log/activity_log_unittest.cc b/chrome/browser/extensions/activity_log/activity_log_unittest.cc
index b187343..0a22195 100644
--- a/chrome/browser/extensions/activity_log/activity_log_unittest.cc
+++ b/chrome/browser/extensions/activity_log/activity_log_unittest.cc
@@ -27,7 +27,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/activity_log/counting_policy_unittest.cc b/chrome/browser/extensions/activity_log/counting_policy_unittest.cc
index 2823812..371b913 100644
--- a/chrome/browser/extensions/activity_log/counting_policy_unittest.cc
+++ b/chrome/browser/extensions/activity_log/counting_policy_unittest.cc
@@ -25,7 +25,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/activity_log/fullstream_ui_policy_unittest.cc b/chrome/browser/extensions/activity_log/fullstream_ui_policy_unittest.cc
index 493469c..188a52a 100644
--- a/chrome/browser/extensions/activity_log/fullstream_ui_policy_unittest.cc
+++ b/chrome/browser/extensions/activity_log/fullstream_ui_policy_unittest.cc
@@ -24,7 +24,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/api/autotest_private/autotest_private_api.cc b/chrome/browser/extensions/api/autotest_private/autotest_private_api.cc
index e2a12d2..da360aa 100644
--- a/chrome/browser/extensions/api/autotest_private/autotest_private_api.cc
+++ b/chrome/browser/extensions/api/autotest_private/autotest_private_api.cc
@@ -23,10 +23,10 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/lock/screen_locker.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/session_manager_client.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 namespace extensions {
@@ -96,7 +96,8 @@ bool AutotestPrivateLoginStatusFunction::RunSync() {
 
   base::DictionaryValue* result(new base::DictionaryValue);
 #if defined(OS_CHROMEOS)
-  const chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  const user_manager::UserManager* user_manager =
+      user_manager::UserManager::Get();
   const bool is_screen_locked =
       !!chromeos::ScreenLocker::default_screen_locker();
 
diff --git a/chrome/browser/extensions/api/braille_display_private/braille_display_private_apitest.cc b/chrome/browser/extensions/api/braille_display_private/braille_display_private_apitest.cc
index ae2300c..41e9dcb 100644
--- a/chrome/browser/extensions/api/braille_display_private/braille_display_private_apitest.cc
+++ b/chrome/browser/extensions/api/braille_display_private/braille_display_private_apitest.cc
@@ -13,7 +13,6 @@
 #include "chrome/browser/chromeos/accessibility/accessibility_manager.h"
 #include "chrome/browser/chromeos/login/lock/screen_locker.h"
 #include "chrome/browser/chromeos/login/lock/screen_locker_tester.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/api/braille_display_private/braille_controller_brlapi.h"
 #include "chrome/browser/extensions/api/braille_display_private/braille_display_private_api.h"
@@ -23,6 +22,7 @@
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/test/base/testing_profile.h"
 #include "chromeos/chromeos_switches.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/test/test_utils.h"
@@ -30,7 +30,7 @@
 
 using chromeos::ProfileHelper;
 using chromeos::ScreenLocker;
-using chromeos::UserManager;
+using user_manager::UserManager;
 using chromeos::test::ScreenLockerTester;
 using content::BrowserThread;
 
@@ -327,8 +327,9 @@ IN_PROC_BROWSER_TEST_F(BrailleDisplayPrivateAPIUserTest,
                        KeyEventOnLockScreen) {
   scoped_ptr<ScreenLockerTester> tester(ScreenLocker::GetTester());
   // Log in.
-  UserManager::Get()->UserLoggedIn(kTestUserName, kTestUserName, true);
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->UserLoggedIn(
+      kTestUserName, kTestUserName, true);
+  user_manager::UserManager::Get()->SessionStarted();
   Profile* profile = ProfileManager::GetActiveUserProfile();
   ASSERT_FALSE(
       ProfileHelper::GetSigninProfile()->IsSameProfile(profile))
diff --git a/chrome/browser/extensions/api/feedback_private/feedback_service_chromeos.cc b/chrome/browser/extensions/api/feedback_private/feedback_service_chromeos.cc
index 84bec47..94cd0e3 100644
--- a/chrome/browser/extensions/api/feedback_private/feedback_service_chromeos.cc
+++ b/chrome/browser/extensions/api/feedback_private/feedback_service_chromeos.cc
@@ -8,8 +8,8 @@
 #include "base/memory/weak_ptr.h"
 #include "base/metrics/statistics_recorder.h"
 #include "base/values.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 
 namespace extensions {
 
@@ -41,7 +41,7 @@ FeedbackServiceImpl::~FeedbackServiceImpl() {
 }
 
 std::string FeedbackServiceImpl::GetUserEmail() {
-  const chromeos::UserManager* manager = chromeos::UserManager::Get();
+  const user_manager::UserManager* manager = user_manager::UserManager::Get();
   const user_manager::User* user = manager ? manager->GetActiveUser() : NULL;
   return user ? user->display_email() : std::string();
 }
diff --git a/chrome/browser/extensions/api/identity/identity_api.cc b/chrome/browser/extensions/api/identity/identity_api.cc
index 26c54c1..58c41aa 100644
--- a/chrome/browser/extensions/api/identity/identity_api.cc
+++ b/chrome/browser/extensions/api/identity/identity_api.cc
@@ -40,10 +40,10 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/session/user_session_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/settings/device_oauth2_token_service.h"
 #include "chrome/browser/chromeos/settings/device_oauth2_token_service_factory.h"
+#include "components/user_manager/user_manager.h"
 #include "google_apis/gaia/gaia_constants.h"
 #endif
 
@@ -367,7 +367,7 @@ bool IdentityGetAuthTokenFunction::RunAsync() {
 #if defined(OS_CHROMEOS)
   policy::BrowserPolicyConnectorChromeOS* connector =
       g_browser_process->platform_part()->browser_policy_connector_chromeos();
-  if (chromeos::UserManager::Get()->IsLoggedInAsKioskApp() &&
+  if (user_manager::UserManager::Get()->IsLoggedInAsKioskApp() &&
       connector->IsEnterpriseManaged()) {
     StartMintTokenFlow(IdentityMintRequestQueue::MINT_TYPE_NONINTERACTIVE);
     return true;
@@ -491,7 +491,7 @@ void IdentityGetAuthTokenFunction::StartMintToken(
       case IdentityTokenCacheValue::CACHE_STATUS_NOTFOUND:
 #if defined(OS_CHROMEOS)
         // Always force minting token for ChromeOS kiosk app.
-        if (chromeos::UserManager::Get()->IsLoggedInAsKioskApp()) {
+        if (user_manager::UserManager::Get()->IsLoggedInAsKioskApp()) {
           gaia_mint_token_mode_ = OAuth2MintTokenFlow::MODE_MINT_TOKEN_FORCE;
           policy::BrowserPolicyConnectorChromeOS* connector =
               g_browser_process->platform_part()
diff --git a/chrome/browser/extensions/api/image_writer_private/operation_manager_unittest.cc b/chrome/browser/extensions/api/image_writer_private/operation_manager_unittest.cc
index dbda8b0..3bd5200 100644
--- a/chrome/browser/extensions/api/image_writer_private/operation_manager_unittest.cc
+++ b/chrome/browser/extensions/api/image_writer_private/operation_manager_unittest.cc
@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 
 #include "base/command_line.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/extensions/api/image_writer_private/error_messages.h"
 #include "chrome/browser/extensions/api/image_writer_private/operation_manager.h"
 #include "chrome/browser/extensions/api/image_writer_private/test_utils.h"
@@ -14,7 +13,7 @@
 #include "extensions/browser/event_router.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/api/input/input.cc b/chrome/browser/extensions/api/input/input.cc
index a3939ad..b9f4b1e 100644
--- a/chrome/browser/extensions/api/input/input.cc
+++ b/chrome/browser/extensions/api/input/input.cc
@@ -21,7 +21,7 @@
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/lock/screen_locker.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif  // OS_CHROMEOS
 
 #if defined(USE_ASH)
@@ -177,10 +177,10 @@ bool VirtualKeyboardPrivateOpenSettingsFunction::RunSync() {
 #if defined(OS_CHROMEOS)
   // Do not try to open language options page if user is not logged in or
   // locked.
-  if (!chromeos::UserManager::Get()->IsUserLoggedIn() ||
+  if (!user_manager::UserManager::Get()->IsUserLoggedIn() ||
       chromeos::UserAddingScreen::Get()->IsRunning() ||
       (chromeos::ScreenLocker::default_screen_locker() &&
-          chromeos::ScreenLocker::default_screen_locker()->locked()))
+       chromeos::ScreenLocker::default_screen_locker()->locked()))
     return true;
 #endif  // OS_CHROMEOS
 
diff --git a/chrome/browser/extensions/api/input_ime/input_ime_api.cc b/chrome/browser/extensions/api/input_ime/input_ime_api.cc
index a7b0fdf..1f75f9f 100644
--- a/chrome/browser/extensions/api/input_ime/input_ime_api.cc
+++ b/chrome/browser/extensions/api/input_ime/input_ime_api.cc
@@ -9,7 +9,6 @@
 #include "chrome/browser/chromeos/input_method/input_method_engine.h"
 #include "chrome/browser/chromeos/login/lock/screen_locker.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/profiles/profile_manager.h"
diff --git a/chrome/browser/extensions/api/networking_private/networking_private_apitest.cc b/chrome/browser/extensions/api/networking_private/networking_private_apitest.cc
index 33f1c9c..19f437e 100644
--- a/chrome/browser/extensions/api/networking_private/networking_private_apitest.cc
+++ b/chrome/browser/extensions/api/networking_private/networking_private_apitest.cc
@@ -7,10 +7,10 @@
 #include "base/command_line.h"
 #include "base/macros.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/extensions/extension_apitest.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "extensions/common/switches.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
@@ -188,7 +188,7 @@ class ExtensionNetworkingPrivateApiTest
   }
 
   void InitializeSanitizedUsername() {
-    chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+    user_manager::UserManager* user_manager = user_manager::UserManager::Get();
     user_manager::User* user = user_manager->GetActiveUser();
     CHECK(user);
     std::string userhash;
diff --git a/chrome/browser/extensions/api/runtime/chrome_runtime_api_delegate.cc b/chrome/browser/extensions/api/runtime/chrome_runtime_api_delegate.cc
index 97098b8..767b444 100644
--- a/chrome/browser/extensions/api/runtime/chrome_runtime_api_delegate.cc
+++ b/chrome/browser/extensions/api/runtime/chrome_runtime_api_delegate.cc
@@ -22,9 +22,9 @@
 #include "extensions/common/api/runtime.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/power_manager_client.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using extensions::Extension;
@@ -226,7 +226,7 @@ bool ChromeRuntimeAPIDelegate::GetPlatformInfo(PlatformInfo* info) {
 
 bool ChromeRuntimeAPIDelegate::RestartDevice(std::string* error_message) {
 #if defined(OS_CHROMEOS)
-  if (chromeos::UserManager::Get()->IsLoggedInAsKioskApp()) {
+  if (user_manager::UserManager::Get()->IsLoggedInAsKioskApp()) {
     chromeos::DBusThreadManager::Get()
         ->GetPowerManagerClient()
         ->RequestRestart();
diff --git a/chrome/browser/extensions/component_loader.cc b/chrome/browser/extensions/component_loader.cc
index ec60802..ac35c2b6 100644
--- a/chrome/browser/extensions/component_loader.cc
+++ b/chrome/browser/extensions/component_loader.cc
@@ -17,6 +17,7 @@
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/chrome_version_info.h"
 #include "chrome/common/extensions/extension_constants.h"
+#include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/plugin_service.h"
 #include "extensions/common/extension.h"
@@ -40,7 +41,6 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/accessibility/accessibility_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chromeos/chromeos_switches.h"
 #include "content/public/browser/site_instance.h"
 #include "content/public/browser/storage_partition.h"
diff --git a/chrome/browser/extensions/crx_installer.cc b/chrome/browser/extensions/crx_installer.cc
index 2228271..9823d4e 100644
--- a/chrome/browser/extensions/crx_installer.cc
+++ b/chrome/browser/extensions/crx_installer.cc
@@ -63,7 +63,7 @@
 #include "ui/base/l10n/l10n_util.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using base::UserMetricsAction;
@@ -574,7 +574,7 @@ void CrxInstaller::ConfirmInstall() {
   if (KioskModeInfo::IsKioskOnly(install_checker_.extension())) {
     bool in_kiosk_mode = false;
 #if defined(OS_CHROMEOS)
-    chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+    user_manager::UserManager* user_manager = user_manager::UserManager::Get();
     in_kiosk_mode = user_manager && user_manager->IsLoggedInAsKioskApp();
 #endif
     if (!in_kiosk_mode) {
diff --git a/chrome/browser/extensions/crx_installer_browsertest.cc b/chrome/browser/extensions/crx_installer_browsertest.cc
index aeb7313..1ae57dd 100644
--- a/chrome/browser/extensions/crx_installer_browsertest.cc
+++ b/chrome/browser/extensions/crx_installer_browsertest.cc
@@ -37,7 +37,7 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/extensions/extension_assets_manager_chromeos.h"
 #include "chromeos/chromeos_switches.h"
 #endif
diff --git a/chrome/browser/extensions/extension_action_icon_factory_unittest.cc b/chrome/browser/extensions/extension_action_icon_factory_unittest.cc
index 748eec2..f163300 100644
--- a/chrome/browser/extensions/extension_action_icon_factory_unittest.cc
+++ b/chrome/browser/extensions/extension_action_icon_factory_unittest.cc
@@ -26,7 +26,7 @@
 #include "ui/gfx/skia_util.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/extension_assets_manager_chromeos.cc b/chrome/browser/extensions/extension_assets_manager_chromeos.cc
index e7e3d92..e74842b 100644
--- a/chrome/browser/extensions/extension_assets_manager_chromeos.cc
+++ b/chrome/browser/extensions/extension_assets_manager_chromeos.cc
@@ -16,13 +16,13 @@
 #include "base/sequenced_task_runner.h"
 #include "base/sys_info.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/extensions/manifest_url_handler.h"
 #include "chromeos/chromeos_switches.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "extensions/browser/extension_prefs.h"
 #include "extensions/browser/extension_system.h"
@@ -281,7 +281,7 @@ void ExtensionAssetsManagerChromeOS::CheckSharedExtension(
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
   const std::string& user_id = profile->GetProfileName();
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (!user_manager) {
     NOTREACHED();
     return;
@@ -497,7 +497,7 @@ bool ExtensionAssetsManagerChromeOS::CleanUpExtension(
     const std::string& id,
     base::DictionaryValue* extension_info,
     std::multimap<std::string, base::FilePath>* live_extension_paths) {
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (!user_manager) {
     NOTREACHED();
     return false;
diff --git a/chrome/browser/extensions/extension_garbage_collector_chromeos.cc b/chrome/browser/extensions/extension_garbage_collector_chromeos.cc
index d4a2d92..e737cc0 100644
--- a/chrome/browser/extensions/extension_garbage_collector_chromeos.cc
+++ b/chrome/browser/extensions/extension_garbage_collector_chromeos.cc
@@ -2,11 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/browser/extensions/extension_garbage_collector_chromeos.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/extension_assets_manager_chromeos.h"
+#include "chrome/browser/extensions/extension_garbage_collector_chromeos.h"
 #include "chrome/browser/extensions/extension_service.h"
+#include "components/user_manager/user_manager.h"
 #include "extensions/browser/extension_system.h"
 
 namespace extensions {
@@ -49,7 +49,7 @@ void ExtensionGarbageCollectorChromeOS::GarbageCollectExtensions() {
 }
 
 bool ExtensionGarbageCollectorChromeOS::CanGarbageCollectSharedExtensions() {
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (!user_manager) {
     NOTREACHED();
     return false;
diff --git a/chrome/browser/extensions/extension_garbage_collector_chromeos_unittest.cc b/chrome/browser/extensions/extension_garbage_collector_chromeos_unittest.cc
index fea341eb..ea6451e 100644
--- a/chrome/browser/extensions/extension_garbage_collector_chromeos_unittest.cc
+++ b/chrome/browser/extensions/extension_garbage_collector_chromeos_unittest.cc
@@ -9,7 +9,7 @@
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/values.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/extension_assets_manager_chromeos.h"
 #include "chrome/browser/extensions/extension_garbage_collector_chromeos.h"
@@ -20,6 +20,7 @@
 #include "chrome/test/base/testing_browser_process.h"
 #include "chrome/test/base/testing_profile.h"
 #include "chromeos/login/user_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/plugin_service.h"
 #include "extensions/browser/extension_prefs.h"
@@ -140,7 +141,7 @@ class ExtensionGarbageCollectorChromeOSUnitTest
 
   chromeos::FakeUserManager* GetFakeUserManager() {
     return static_cast<chromeos::FakeUserManager*>(
-        chromeos::UserManager::Get());
+        user_manager::UserManager::Get());
   }
 
  private:
diff --git a/chrome/browser/extensions/extension_gcm_app_handler_unittest.cc b/chrome/browser/extensions/extension_gcm_app_handler_unittest.cc
index ffef228..21027f3 100644
--- a/chrome/browser/extensions/extension_gcm_app_handler_unittest.cc
+++ b/chrome/browser/extensions/extension_gcm_app_handler_unittest.cc
@@ -53,7 +53,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/extension_service_test_base.h b/chrome/browser/extensions/extension_service_test_base.h
index dea4f4f..cf0785d 100644
--- a/chrome/browser/extensions/extension_service_test_base.h
+++ b/chrome/browser/extensions/extension_service_test_base.h
@@ -14,7 +14,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/extension_service_unittest.cc b/chrome/browser/extensions/extension_service_unittest.cc
index 4c475ff..20b589f 100644
--- a/chrome/browser/extensions/extension_service_unittest.cc
+++ b/chrome/browser/extensions/extension_service_unittest.cc
@@ -129,7 +129,7 @@
 #include "webkit/common/database/database_identifier.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/extension_system_impl.cc b/chrome/browser/extensions/extension_system_impl.cc
index 9804b81..bb4617a 100644
--- a/chrome/browser/extensions/extension_system_impl.cc
+++ b/chrome/browser/extensions/extension_system_impl.cc
@@ -71,12 +71,12 @@
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/app_mode/app_mode_utils.h"
 #include "chrome/browser/chromeos/extensions/device_local_account_management_policy_provider.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/device_local_account.h"
 #include "chrome/browser/extensions/extension_assets_manager_chromeos.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/login/login_state.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using content::BrowserThread;
@@ -126,7 +126,7 @@ void ExtensionSystemImpl::Shared::InitPrefs() {
 
 #if defined(OS_CHROMEOS)
   const user_manager::User* user =
-      chromeos::UserManager::Get()->GetActiveUser();
+      user_manager::UserManager::Get()->GetActiveUser();
   policy::DeviceLocalAccount::Type device_local_account_type;
   if (user && policy::IsDeviceLocalAccountUser(user->email(),
                                                &device_local_account_type)) {
diff --git a/chrome/browser/extensions/extension_ui_unittest.cc b/chrome/browser/extensions/extension_ui_unittest.cc
index 5ec8f7b..09f66c4 100644
--- a/chrome/browser/extensions/extension_ui_unittest.cc
+++ b/chrome/browser/extensions/extension_ui_unittest.cc
@@ -19,7 +19,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/extension_web_ui_unittest.cc b/chrome/browser/extensions/extension_web_ui_unittest.cc
index 7d69656..fb3bee9 100644
--- a/chrome/browser/extensions/extension_web_ui_unittest.cc
+++ b/chrome/browser/extensions/extension_web_ui_unittest.cc
@@ -16,7 +16,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/external_provider_impl.cc b/chrome/browser/extensions/external_provider_impl.cc
index 79181b8..271d0a4 100644
--- a/chrome/browser/extensions/external_provider_impl.cc
+++ b/chrome/browser/extensions/external_provider_impl.cc
@@ -37,13 +37,13 @@
 #include "chrome/browser/chromeos/app_mode/kiosk_app_manager.h"
 #include "chrome/browser/chromeos/customization_document.h"
 #include "chrome/browser/chromeos/extensions/device_local_account_external_policy_loader.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/app_pack_updater.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_local_account.h"
 #include "chrome/browser/chromeos/policy/device_local_account_policy_service.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #else
 #include "chrome/browser/extensions/default_apps.h"
 #endif
@@ -437,7 +437,7 @@ void ExternalProviderImpl::CreateExternalProviders(
   bool is_chromeos_demo_session = false;
   int bundled_extension_creation_flags = Extension::NO_FLAGS;
 #if defined(OS_CHROMEOS)
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   is_chromeos_demo_session =
       user_manager && user_manager->IsLoggedInAsDemoUser() &&
       connector->GetDeviceMode() == policy::DEVICE_MODE_RETAIL_KIOSK;
diff --git a/chrome/browser/extensions/external_provider_impl_chromeos_unittest.cc b/chrome/browser/extensions/external_provider_impl_chromeos_unittest.cc
index c88ecce..bc90c09 100644
--- a/chrome/browser/extensions/external_provider_impl_chromeos_unittest.cc
+++ b/chrome/browser/extensions/external_provider_impl_chromeos_unittest.cc
@@ -12,6 +12,7 @@
 #include "chrome/browser/chromeos/app_mode/kiosk_app_manager.h"
 #include "chrome/browser/chromeos/customization_document.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_service_test_base.h"
 #include "chrome/common/chrome_paths.h"
diff --git a/chrome/browser/extensions/external_provider_impl_unittest.cc b/chrome/browser/extensions/external_provider_impl_unittest.cc
index f74949c..f9991cb 100644
--- a/chrome/browser/extensions/external_provider_impl_unittest.cc
+++ b/chrome/browser/extensions/external_provider_impl_unittest.cc
@@ -32,6 +32,7 @@
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/customization_document.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chromeos/system/mock_statistics_provider.h"
 #include "chromeos/system/statistics_provider.h"
 #endif
diff --git a/chrome/browser/extensions/page_action_controller_unittest.cc b/chrome/browser/extensions/page_action_controller_unittest.cc
index 5d96b18..33e0c84 100644
--- a/chrome/browser/extensions/page_action_controller_unittest.cc
+++ b/chrome/browser/extensions/page_action_controller_unittest.cc
@@ -21,7 +21,7 @@
 #include "extensions/common/value_builder.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/test_extension_environment.h b/chrome/browser/extensions/test_extension_environment.h
index a8afc858..57136588 100644
--- a/chrome/browser/extensions/test_extension_environment.h
+++ b/chrome/browser/extensions/test_extension_environment.h
@@ -10,7 +10,7 @@
 #include "content/public/test/test_browser_thread_bundle.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/updater/extension_updater_unittest.cc b/chrome/browser/extensions/updater/extension_updater_unittest.cc
index 874dca1..b6ebb83 100644
--- a/chrome/browser/extensions/updater/extension_updater_unittest.cc
+++ b/chrome/browser/extensions/updater/extension_updater_unittest.cc
@@ -67,7 +67,7 @@
 #include "url/third_party/mozilla/url_parse.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/extensions/zipfile_installer_unittest.cc b/chrome/browser/extensions/zipfile_installer_unittest.cc
index 63ea3c7..f26d836 100644
--- a/chrome/browser/extensions/zipfile_installer_unittest.cc
+++ b/chrome/browser/extensions/zipfile_installer_unittest.cc
@@ -25,7 +25,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/invalidation/profile_invalidation_provider_factory.cc b/chrome/browser/invalidation/profile_invalidation_provider_factory.cc
index f54a63b..3c1bc71 100644
--- a/chrome/browser/invalidation/profile_invalidation_provider_factory.cc
+++ b/chrome/browser/invalidation/profile_invalidation_provider_factory.cc
@@ -36,11 +36,11 @@
 
 #if defined(OS_CHROMEOS)
 #include "base/files/file_path.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/settings/device_identity_provider.h"
 #include "chrome/browser/chromeos/settings/device_oauth2_token_service_factory.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 namespace invalidation {
@@ -53,9 +53,9 @@ ProfileInvalidationProvider* ProfileInvalidationProviderFactory::GetForProfile(
   // when this method is called during the creation of the sign-in profile
   // itself. Using ProfileHelper::GetSigninProfileDir() is safe because it does
   // not try to access the sign-in profile.
-  if (profile->GetPath() == chromeos::ProfileHelper::GetSigninProfileDir()||
-      (chromeos::UserManager::IsInitialized() &&
-       chromeos::UserManager::Get()->IsLoggedInAsGuest())) {
+  if (profile->GetPath() == chromeos::ProfileHelper::GetSigninProfileDir() ||
+      (user_manager::UserManager::IsInitialized() &&
+       user_manager::UserManager::Get()->IsLoggedInAsGuest())) {
     // The Chrome OS login and Chrome OS guest profiles do not have GAIA
     // credentials and do not support invalidation.
     return NULL;
@@ -110,8 +110,8 @@ KeyedService* ProfileInvalidationProviderFactory::BuildServiceInstanceFor(
 #if defined(OS_CHROMEOS)
   policy::BrowserPolicyConnectorChromeOS* connector =
       g_browser_process->platform_part()->browser_policy_connector_chromeos();
-  if (chromeos::UserManager::IsInitialized() &&
-      chromeos::UserManager::Get()->IsLoggedInAsKioskApp() &&
+  if (user_manager::UserManager::IsInitialized() &&
+      user_manager::UserManager::Get()->IsLoggedInAsKioskApp() &&
       connector->IsEnterpriseManaged()) {
     identity_provider.reset(new chromeos::DeviceIdentityProvider(
         chromeos::DeviceOAuth2TokenServiceFactory::Get()));
diff --git a/chrome/browser/invalidation/profile_invalidation_provider_factory_browsertest.cc b/chrome/browser/invalidation/profile_invalidation_provider_factory_browsertest.cc
index d4e7003..b30ca78 100644
--- a/chrome/browser/invalidation/profile_invalidation_provider_factory_browsertest.cc
+++ b/chrome/browser/invalidation/profile_invalidation_provider_factory_browsertest.cc
@@ -14,6 +14,7 @@
 #include "chromeos/login/user_names.h"
 #include "components/invalidation/invalidation_service.h"
 #include "components/invalidation/profile_invalidation_provider.h"
+#include "components/user_manager/user_manager.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace invalidation {
@@ -114,7 +115,7 @@ void ProfileInvalidationProviderFactoryGuestBrowserTest::SetUpCommandLine(
 // the guest profile while a guest session is in progress.
 IN_PROC_BROWSER_TEST_F(ProfileInvalidationProviderFactoryGuestBrowserTest,
                        NoInvalidationService) {
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   EXPECT_TRUE(user_manager->IsLoggedInAsGuest());
   Profile* guest_profile =
       chromeos::ProfileHelper::Get()
diff --git a/chrome/browser/io_thread.cc b/chrome/browser/io_thread.cc
index e954d4a..664a507 100644
--- a/chrome/browser/io_thread.cc
+++ b/chrome/browser/io_thread.cc
@@ -104,7 +104,6 @@
 #endif  // defined(SPDY_PROXY_AUTH_ORIGIN)
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/net/cert_verify_proc_chromeos.h"
 #include "chromeos/network/host_resolver_impl_chromeos.h"
 #endif
diff --git a/chrome/browser/lifetime/application_lifetime.cc b/chrome/browser/lifetime/application_lifetime.cc
index 4c10890..f02bd06 100644
--- a/chrome/browser/lifetime/application_lifetime.cc
+++ b/chrome/browser/lifetime/application_lifetime.cc
@@ -41,7 +41,6 @@
 #if defined(OS_CHROMEOS)
 #include "base/sys_info.h"
 #include "chrome/browser/chromeos/boot_times_loader.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/session_manager_client.h"
 #include "chromeos/dbus/update_engine_client.h"
diff --git a/chrome/browser/media/media_stream_devices_controller.cc b/chrome/browser/media/media_stream_devices_controller.cc
index 431af98..dd9ca2c 100644
--- a/chrome/browser/media/media_stream_devices_controller.cc
+++ b/chrome/browser/media/media_stream_devices_controller.cc
@@ -31,7 +31,7 @@
 #include "ui/base/l10n/l10n_util.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using content::BrowserThread;
@@ -86,7 +86,8 @@ bool IsInKioskMode() {
     return true;
 
 #if defined(OS_CHROMEOS)
-  const chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  const user_manager::UserManager* user_manager =
+      user_manager::UserManager::Get();
   return user_manager && user_manager->IsLoggedInAsKioskApp();
 #else
   return false;
diff --git a/chrome/browser/media_galleries/gallery_watch_manager_unittest.cc b/chrome/browser/media_galleries/gallery_watch_manager_unittest.cc
index fe3b9f2..9599b3a 100644
--- a/chrome/browser/media_galleries/gallery_watch_manager_unittest.cc
+++ b/chrome/browser/media_galleries/gallery_watch_manager_unittest.cc
@@ -25,7 +25,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/media_galleries/media_file_system_registry_unittest.cc b/chrome/browser/media_galleries/media_file_system_registry_unittest.cc
index c80efdc..a43723f 100644
--- a/chrome/browser/media_galleries/media_file_system_registry_unittest.cc
+++ b/chrome/browser/media_galleries/media_file_system_registry_unittest.cc
@@ -49,7 +49,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/media_galleries/media_galleries_permission_controller_unittest.cc b/chrome/browser/media_galleries/media_galleries_permission_controller_unittest.cc
index ba975b5..7246aee 100644
--- a/chrome/browser/media_galleries/media_galleries_permission_controller_unittest.cc
+++ b/chrome/browser/media_galleries/media_galleries_permission_controller_unittest.cc
@@ -22,7 +22,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/media_galleries/media_galleries_preferences_unittest.cc b/chrome/browser/media_galleries/media_galleries_preferences_unittest.cc
index 1a1f8c9..e3a4e8f 100644
--- a/chrome/browser/media_galleries/media_galleries_preferences_unittest.cc
+++ b/chrome/browser/media_galleries/media_galleries_preferences_unittest.cc
@@ -37,7 +37,7 @@
 #include "ui/base/l10n/l10n_util.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/media_galleries/media_galleries_scan_result_controller_unittest.cc b/chrome/browser/media_galleries/media_galleries_scan_result_controller_unittest.cc
index f345c3b..026715d 100644
--- a/chrome/browser/media_galleries/media_galleries_scan_result_controller_unittest.cc
+++ b/chrome/browser/media_galleries/media_galleries_scan_result_controller_unittest.cc
@@ -25,7 +25,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/media_galleries/media_scan_manager_unittest.cc b/chrome/browser/media_galleries/media_scan_manager_unittest.cc
index 9964aff..fa10586 100644
--- a/chrome/browser/media_galleries/media_scan_manager_unittest.cc
+++ b/chrome/browser/media_galleries/media_scan_manager_unittest.cc
@@ -27,7 +27,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/metrics/chromeos_metrics_provider.cc b/chrome/browser/metrics/chromeos_metrics_provider.cc
index ef732c0..eb90cfe 100644
--- a/chrome/browser/metrics/chromeos_metrics_provider.cc
+++ b/chrome/browser/metrics/chromeos_metrics_provider.cc
@@ -10,11 +10,11 @@
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/system/statistics_provider.h"
 #include "components/metrics/metrics_service.h"
 #include "components/metrics/proto/chrome_user_metrics_extension.pb.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "device/bluetooth/bluetooth_adapter.h"
 #include "device/bluetooth/bluetooth_adapter_factory.h"
@@ -128,10 +128,10 @@ void ChromeOSMetricsProvider::LogCrash(const std::string& crash_type) {
 
 void ChromeOSMetricsProvider::OnDidCreateMetricsLog() {
   registered_user_count_at_log_initialization_ = false;
-  if (chromeos::UserManager::IsInitialized()) {
+  if (user_manager::UserManager::IsInitialized()) {
     registered_user_count_at_log_initialization_ = true;
     user_count_at_log_initialization_ =
-        chromeos::UserManager::Get()->GetLoggedInUsers().size();
+        user_manager::UserManager::Get()->GetLoggedInUsers().size();
   }
 }
 
@@ -269,8 +269,9 @@ void ChromeOSMetricsProvider::WriteBluetoothProto(
 
 void ChromeOSMetricsProvider::UpdateMultiProfileUserCount(
     metrics::SystemProfileProto* system_profile_proto) {
-  if (chromeos::UserManager::IsInitialized()) {
-    size_t user_count = chromeos::UserManager::Get()->GetLoggedInUsers().size();
+  if (user_manager::UserManager::IsInitialized()) {
+    size_t user_count =
+        user_manager::UserManager::Get()->GetLoggedInUsers().size();
 
     // We invalidate the user count if it changed while the log was open.
     if (registered_user_count_at_log_initialization_ &&
diff --git a/chrome/browser/metrics/chromeos_metrics_provider_unittest.cc b/chrome/browser/metrics/chromeos_metrics_provider_unittest.cc
index 21f5e16..a9ae53ef 100644
--- a/chrome/browser/metrics/chromeos_metrics_provider_unittest.cc
+++ b/chrome/browser/metrics/chromeos_metrics_provider_unittest.cc
@@ -8,7 +8,7 @@
 
 #include "base/basictypes.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/metrics/chromeos_metrics_provider.h"
 #include "chromeos/dbus/fake_bluetooth_adapter_client.h"
 #include "chromeos/dbus/fake_bluetooth_agent_manager_client.h"
@@ -21,6 +21,7 @@
 #include "chromeos/dbus/power_manager_client.h"
 #include "chromeos/login/login_state.h"
 #include "components/metrics/proto/system_profile.pb.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/test/test_browser_thread_bundle.h"
 #include "content/public/test/test_utils.h"
 #include "testing/gtest/include/gtest/gtest.h"
diff --git a/chrome/browser/net/nss_context_chromeos_browsertest.cc b/chrome/browser/net/nss_context_chromeos_browsertest.cc
index d77c64f..c1aec35 100644
--- a/chrome/browser/net/nss_context_chromeos_browsertest.cc
+++ b/chrome/browser/net/nss_context_chromeos_browsertest.cc
@@ -9,9 +9,9 @@
 #include "chrome/browser/chromeos/login/login_manager_test.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "net/cert/nss_cert_database.h"
 
@@ -131,7 +131,7 @@ IN_PROC_BROWSER_TEST_F(NSSContextChromeOSBrowserTest, PRE_TwoUsers) {
 }
 
 IN_PROC_BROWSER_TEST_F(NSSContextChromeOSBrowserTest, TwoUsers) {
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
   // Log in first user and get their DB.
   LoginUser(kTestUser1);
diff --git a/chrome/browser/notifications/message_center_settings_controller.cc b/chrome/browser/notifications/message_center_settings_controller.cc
index a163942..f0bc5fb 100644
--- a/chrome/browser/notifications/message_center_settings_controller.cc
+++ b/chrome/browser/notifications/message_center_settings_controller.cc
@@ -141,16 +141,16 @@ MessageCenterSettingsController::MessageCenterSettingsController(
 
 #if defined(OS_CHROMEOS)
   // UserManager may not exist in some tests.
-  if (chromeos::UserManager::IsInitialized())
-    chromeos::UserManager::Get()->AddSessionStateObserver(this);
+  if (user_manager::UserManager::IsInitialized())
+    user_manager::UserManager::Get()->AddSessionStateObserver(this);
 #endif
 }
 
 MessageCenterSettingsController::~MessageCenterSettingsController() {
 #if defined(OS_CHROMEOS)
   // UserManager may not exist in some tests.
-  if (chromeos::UserManager::IsInitialized())
-    chromeos::UserManager::Get()->RemoveSessionStateObserver(this);
+  if (user_manager::UserManager::IsInitialized())
+    user_manager::UserManager::Get()->RemoveSessionStateObserver(this);
 #endif
 }
 
@@ -446,7 +446,7 @@ void MessageCenterSettingsController::CreateNotifierGroupForGuestLogin() {
   if (!notifier_groups_.empty())
     return;
 
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   // |notifier_groups_| can be empty in login screen too.
   if (!user_manager->IsLoggedInAsGuest())
     return;
@@ -488,8 +488,9 @@ void MessageCenterSettingsController::RebuildNotifierGroups() {
 #if defined(OS_CHROMEOS)
     // Allows the active user only.
     // UserManager may not exist in some tests.
-    if (chromeos::UserManager::IsInitialized()) {
-      chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+    if (user_manager::UserManager::IsInitialized()) {
+      user_manager::UserManager* user_manager =
+          user_manager::UserManager::Get();
       if (chromeos::ProfileHelper::Get()->GetUserByProfile(group->profile()) !=
           user_manager->GetActiveUser()) {
         continue;
@@ -508,8 +509,8 @@ void MessageCenterSettingsController::RebuildNotifierGroups() {
 #if defined(OS_CHROMEOS)
   // ChromeOS guest login cannot get the profile from the for-loop above, so
   // get the group here.
-  if (notifier_groups_.empty() && chromeos::UserManager::IsInitialized() &&
-      chromeos::UserManager::Get()->IsLoggedInAsGuest()) {
+  if (notifier_groups_.empty() && user_manager::UserManager::IsInitialized() &&
+      user_manager::UserManager::Get()->IsLoggedInAsGuest()) {
     // Do not invoke CreateNotifierGroupForGuestLogin() directly. In some tests,
     // this method may be called before the primary profile is created, which
     // means ProfileHelper::Get()->GetProfileByUser() will create a new primary
diff --git a/chrome/browser/notifications/message_center_settings_controller.h b/chrome/browser/notifications/message_center_settings_controller.h
index 18a7382..a4abb49 100644
--- a/chrome/browser/notifications/message_center_settings_controller.h
+++ b/chrome/browser/notifications/message_center_settings_controller.h
@@ -23,7 +23,7 @@
 #include "ui/message_center/notifier_settings.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 class Profile;
@@ -47,7 +47,7 @@ class MessageCenterSettingsController
     : public message_center::NotifierSettingsProvider,
       public content::NotificationObserver,
 #if defined(OS_CHROMEOS)
-      public chromeos::UserManager::UserSessionStateObserver,
+      public user_manager::UserManager::UserSessionStateObserver,
 #endif
       public extensions::AppIconLoader::Delegate {
  public:
@@ -79,7 +79,7 @@ class MessageCenterSettingsController
       const std::string* notification_id) OVERRIDE;
 
 #if defined(OS_CHROMEOS)
-  // Overridden from chromeos::UserManager::UserSessionStateObserver.
+  // Overridden from user_manager::UserManager::UserSessionStateObserver.
   virtual void ActiveUserChanged(
       const user_manager::User* active_user) OVERRIDE;
 #endif
diff --git a/chrome/browser/notifications/message_center_settings_controller_unittest.cc b/chrome/browser/notifications/message_center_settings_controller_unittest.cc
index 9046e58..750f29f 100644
--- a/chrome/browser/notifications/message_center_settings_controller_unittest.cc
+++ b/chrome/browser/notifications/message_center_settings_controller_unittest.cc
@@ -18,6 +18,7 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #endif
 
 class MessageCenterSettingsControllerTest : public testing::Test {
@@ -96,7 +97,7 @@ class MessageCenterSettingsControllerChromeOSTest
  private:
   chromeos::FakeUserManager* GetFakeUserManager() {
     return static_cast<chromeos::FakeUserManager*>(
-        chromeos::UserManager::Get());
+        user_manager::UserManager::Get());
   }
 
   scoped_ptr<chromeos::ScopedUserManagerEnabler> user_manager_enabler_;
diff --git a/chrome/browser/performance_monitor/performance_monitor_browsertest.cc b/chrome/browser/performance_monitor/performance_monitor_browsertest.cc
index ee0d5f2..81519c9f 100644
--- a/chrome/browser/performance_monitor/performance_monitor_browsertest.cc
+++ b/chrome/browser/performance_monitor/performance_monitor_browsertest.cc
@@ -45,9 +45,9 @@
 #include "extensions/common/extension.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chromeos/chromeos_switches.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 #if defined(OS_MACOSX)
@@ -359,9 +359,8 @@ class PerformanceMonitorUncleanExitBrowserTest
   virtual void AddSecondUserAccount() {
     // Add second user account for multi-profile test.
     if (GetParam()) {
-      chromeos::UserManager::Get()->UserLoggedIn(kSecondProfileAccount,
-                                                 kSecondProfileHash,
-                                                 false);
+      user_manager::UserManager::Get()->UserLoggedIn(
+          kSecondProfileAccount, kSecondProfileHash, false);
     }
   }
 #endif
diff --git a/chrome/browser/policy/cloud/cloud_policy_browsertest.cc b/chrome/browser/policy/cloud/cloud_policy_browsertest.cc
index 517a560..238fdd1 100644
--- a/chrome/browser/policy/cloud/cloud_policy_browsertest.cc
+++ b/chrome/browser/policy/cloud/cloud_policy_browsertest.cc
@@ -48,7 +48,6 @@
 #include "url/gurl.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos.h"
 #include "chrome/browser/chromeos/policy/user_cloud_policy_manager_factory_chromeos.h"
 #include "chromeos/chromeos_paths.h"
diff --git a/chrome/browser/policy/configuration_policy_handler_list_factory.cc b/chrome/browser/policy/configuration_policy_handler_list_factory.cc
index 6e26e3b..2321a7a 100644
--- a/chrome/browser/policy/configuration_policy_handler_list_factory.cc
+++ b/chrome/browser/policy/configuration_policy_handler_list_factory.cc
@@ -38,10 +38,10 @@
 
 #if defined(OS_CHROMEOS)
 #include "ash/magnifier/magnifier_constants.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/configuration_policy_handler_chromeos.h"
 #include "chromeos/dbus/power_policy_controller.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 #if !defined(OS_ANDROID) && !defined(OS_IOS)
@@ -535,9 +535,9 @@ void GetDeprecatedFeaturesMap(
 
 void PopulatePolicyHandlerParameters(PolicyHandlerParameters* parameters) {
 #if defined(OS_CHROMEOS)
-  if (chromeos::UserManager::IsInitialized()) {
+  if (user_manager::UserManager::IsInitialized()) {
     const user_manager::User* user =
-        chromeos::UserManager::Get()->GetActiveUser();
+        user_manager::UserManager::Get()->GetActiveUser();
     if (user)
       parameters->user_id_hash = user->username_hash();
   }
diff --git a/chrome/browser/policy/profile_policy_connector.cc b/chrome/browser/policy/profile_policy_connector.cc
index 85694c2..cd93a32 100644
--- a/chrome/browser/policy/profile_policy_connector.cc
+++ b/chrome/browser/policy/profile_policy_connector.cc
@@ -20,12 +20,12 @@
 #include "google_apis/gaia/gaia_auth_util.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_cloud_policy_manager_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_local_account_policy_provider.h"
 #include "chrome/browser/chromeos/policy/login_profile_policy_provider.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 namespace policy {
@@ -106,7 +106,8 @@ void ProfilePolicyConnector::Init(
         new LoginProfilePolicyProvider(connector->GetPolicyService()));
   } else {
     // |user| should never be NULL except for the signin profile.
-    is_primary_user_ = user == chromeos::UserManager::Get()->GetPrimaryUser();
+    is_primary_user_ =
+        user == user_manager::UserManager::Get()->GetPrimaryUser();
     special_user_policy_provider_ = DeviceLocalAccountPolicyProvider::Create(
         user->email(),
         connector->GetDeviceLocalAccountPolicyService());
diff --git a/chrome/browser/policy/schema_registry_service_factory.cc b/chrome/browser/policy/schema_registry_service_factory.cc
index 94dbbc8..a2997ab 100644
--- a/chrome/browser/policy/schema_registry_service_factory.cc
+++ b/chrome/browser/policy/schema_registry_service_factory.cc
@@ -14,12 +14,12 @@
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_process_platform_part_chromeos.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_local_account_policy_service.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 namespace policy {
@@ -33,7 +33,7 @@ DeviceLocalAccountPolicyBroker* GetBroker(content::BrowserContext* context) {
   if (chromeos::ProfileHelper::IsSigninProfile(profile))
     return NULL;
 
-  if (!chromeos::UserManager::IsInitialized()) {
+  if (!user_manager::UserManager::IsInitialized()) {
     // Bail out in unit tests that don't have a UserManager.
     return NULL;
   }
diff --git a/chrome/browser/prefs/browser_prefs.cc b/chrome/browser/prefs/browser_prefs.cc
index 525dac2..44ff8a8 100644
--- a/chrome/browser/prefs/browser_prefs.cc
+++ b/chrome/browser/prefs/browser_prefs.cc
@@ -154,8 +154,8 @@
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_sync_observer.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager_impl.h"
 #include "chrome/browser/chromeos/login/users/multi_profile_user_controller.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/chromeos/net/proxy_config_handler.h"
 #include "chrome/browser/chromeos/policy/auto_enrollment_client.h"
@@ -303,6 +303,7 @@ void RegisterLocalState(PrefRegistrySimple* registry) {
   ChromeOSMetricsProvider::RegisterPrefs(registry);
   chromeos::AudioDevicesPrefHandlerImpl::RegisterPrefs(registry);
   chromeos::ChargerReplacementHandler::RegisterPrefs(registry);
+  chromeos::ChromeUserManagerImpl::RegisterPrefs(registry);
   chromeos::DataPromoNotification::RegisterPrefs(registry);
   chromeos::DeviceOAuth2TokenService::RegisterPrefs(registry);
   chromeos::device_settings_cache::RegisterPrefs(registry);
@@ -321,7 +322,6 @@ void RegisterLocalState(PrefRegistrySimple* registry) {
   chromeos::StartupUtils::RegisterPrefs(registry);
   chromeos::system::AutomaticRebootManager::RegisterPrefs(registry);
   chromeos::UserImageManager::RegisterPrefs(registry);
-  chromeos::UserManager::RegisterPrefs(registry);
   chromeos::UserSessionManager::RegisterPrefs(registry);
   chromeos::WallpaperManager::RegisterPrefs(registry);
   chromeos::echo_offer::RegisterPrefs(registry);
diff --git a/chrome/browser/profiles/off_the_record_profile_impl.cc b/chrome/browser/profiles/off_the_record_profile_impl.cc
index 61bb7a6..209ba2a 100644
--- a/chrome/browser/profiles/off_the_record_profile_impl.cc
+++ b/chrome/browser/profiles/off_the_record_profile_impl.cc
@@ -489,8 +489,9 @@ class GuestSessionProfile : public OffTheRecordProfileImpl {
 
   virtual void InitChromeOSPreferences() OVERRIDE {
     chromeos_preferences_.reset(new chromeos::Preferences());
-    chromeos_preferences_->Init(static_cast<PrefServiceSyncable*>(GetPrefs()),
-                                chromeos::UserManager::Get()->GetActiveUser());
+    chromeos_preferences_->Init(
+        static_cast<PrefServiceSyncable*>(GetPrefs()),
+        user_manager::UserManager::Get()->GetActiveUser());
   }
 
  private:
diff --git a/chrome/browser/profiles/profile_impl.cc b/chrome/browser/profiles/profile_impl.cc
index e84f795..d1d6325 100644
--- a/chrome/browser/profiles/profile_impl.cc
+++ b/chrome/browser/profiles/profile_impl.cc
@@ -111,9 +111,9 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/locale_change_guard.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/preferences.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 #if defined(SPDY_PROXY_AUTH_ORIGIN)
@@ -1263,7 +1263,7 @@ void ProfileImpl::ChangeAppLocale(
   if (via != APP_LOCALE_CHANGED_VIA_PUBLIC_SESSION_LOGIN)
     local_state->SetString(prefs::kApplicationLocale, new_locale);
 
-  if (chromeos::UserManager::Get()->GetOwnerEmail() ==
+  if (user_manager::UserManager::Get()->GetOwnerEmail() ==
       chromeos::ProfileHelper::Get()->GetUserByProfile(this)->email())
     local_state->SetString(prefs::kOwnerLocale, new_locale);
 }
diff --git a/chrome/browser/profiles/profile_io_data.cc b/chrome/browser/profiles/profile_io_data.cc
index 1bf14f6..1df3ccd 100644
--- a/chrome/browser/profiles/profile_io_data.cc
+++ b/chrome/browser/profiles/profile_io_data.cc
@@ -108,7 +108,6 @@
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/drive/drive_protocol_handler.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/net/cert_verify_proc_chromeos.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/policy_cert_service.h"
@@ -121,6 +120,7 @@
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/settings/cros_settings_names.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "crypto/nss_util.h"
 #include "crypto/nss_util_internal.h"
 #include "net/cert/multi_threaded_cert_verifier.h"
@@ -223,7 +223,8 @@ class DebugDevToolsInterceptor : public net::URLRequestInterceptor {
 // per-profile.
 //
 // Initialization basically follows these steps:
-// 1) Get some info from chromeos::UserManager about the User for this profile.
+// 1) Get some info from user_manager::UserManager about the User for this
+// profile.
 // 2) Tell nss_util to initialize the software slot for this profile.
 // 3) Wait for the TPM module to be loaded by nss_util if it isn't already.
 // 4) Ask CryptohomeClient which TPM slot id corresponds to this profile.
@@ -366,7 +367,7 @@ void ProfileIOData::InitializeOnUIThread(Profile* profile) {
       supervised_user_service->GetURLFilterForIOThread();
 #endif
 #if defined(OS_CHROMEOS)
-  chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (user_manager) {
     user_manager::User* user =
         chromeos::ProfileHelper::Get()->GetUserByProfile(profile);
diff --git a/chrome/browser/profiles/profile_manager.cc b/chrome/browser/profiles/profile_manager.cc
index 4b0fee3..9d410c5 100644
--- a/chrome/browser/profiles/profile_manager.cc
+++ b/chrome/browser/profiles/profile_manager.cc
@@ -82,13 +82,13 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/browser_process_platform_part_chromeos.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profiles_state.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/dbus/cryptohome_client.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using base::UserMetricsAction;
@@ -313,10 +313,11 @@ std::vector<Profile*> ProfileManager::GetLastOpenedProfiles() {
 Profile* ProfileManager::GetPrimaryUserProfile() {
   ProfileManager* profile_manager = g_browser_process->profile_manager();
 #if defined(OS_CHROMEOS)
-  if (!profile_manager->IsLoggedIn() || !chromeos::UserManager::IsInitialized())
+  if (!profile_manager->IsLoggedIn() ||
+      !user_manager::UserManager::IsInitialized())
     return profile_manager->GetActiveUserOrOffTheRecordProfileFromPath(
         profile_manager->user_data_dir());
-  chromeos::UserManager* manager = chromeos::UserManager::Get();
+  user_manager::UserManager* manager = user_manager::UserManager::Get();
   // Note: The ProfileHelper will take care of guest profiles.
   return chromeos::ProfileHelper::Get()->GetProfileByUserUnsafe(
       manager->GetPrimaryUser());
@@ -331,12 +332,12 @@ Profile* ProfileManager::GetActiveUserProfile() {
   ProfileManager* profile_manager = g_browser_process->profile_manager();
 #if defined(OS_CHROMEOS)
   if (!profile_manager->IsLoggedIn() ||
-      !chromeos::UserManager::IsInitialized()) {
+      !user_manager::UserManager::IsInitialized()) {
     return profile_manager->GetActiveUserOrOffTheRecordProfileFromPath(
         profile_manager->user_data_dir());
   }
 
-  chromeos::UserManager* manager = chromeos::UserManager::Get();
+  user_manager::UserManager* manager = user_manager::UserManager::Get();
   const user_manager::User* user = manager->GetActiveUser();
   // To avoid an endless loop (crbug.com/334098) we have to additionally check
   // if the profile of the user was already created. If the profile was not yet
@@ -1053,7 +1054,7 @@ Profile* ProfileManager::GetActiveUserOrOffTheRecordProfileFromPath(
     // if the login-profile switch is passed so that we can test this.
     if (ShouldGoOffTheRecord(profile))
       return profile->GetOffTheRecordProfile();
-    DCHECK(!chromeos::UserManager::Get()->IsLoggedInAsGuest());
+    DCHECK(!user_manager::UserManager::Get()->IsLoggedInAsGuest());
     return profile;
   }
 
@@ -1066,8 +1067,8 @@ Profile* ProfileManager::GetActiveUserOrOffTheRecordProfileFromPath(
 
   Profile* profile = GetProfile(default_profile_dir);
   // Some unit tests didn't initialize the UserManager.
-  if (chromeos::UserManager::IsInitialized() &&
-      chromeos::UserManager::Get()->IsLoggedInAsGuest())
+  if (user_manager::UserManager::IsInitialized() &&
+      user_manager::UserManager::Get()->IsLoggedInAsGuest())
     return profile->GetOffTheRecordProfile();
   return profile;
 #else
diff --git a/chrome/browser/profiles/profile_manager_unittest.cc b/chrome/browser/profiles/profile_manager_unittest.cc
index 681ce38..b43a973 100644
--- a/chrome/browser/profiles/profile_manager_unittest.cc
+++ b/chrome/browser/profiles/profile_manager_unittest.cc
@@ -46,11 +46,12 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/users/mock_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/login/user_names.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using base::ASCIIToUTF16;
@@ -404,9 +405,10 @@ class ProfileManagerGuestTest : public ProfileManagerTest  {
     cl->AppendSwitch(chromeos::switches::kGuestSession);
     cl->AppendSwitch(::switches::kIncognito);
 
-    chromeos::UserManager::Get()->UserLoggedIn(chromeos::login::kGuestUserName,
-                                               chromeos::login::kGuestUserName,
-                                               false);
+    user_manager::UserManager::Get()->UserLoggedIn(
+        chromeos::login::kGuestUserName,
+        chromeos::login::kGuestUserName,
+        false);
 #endif
   }
 };
diff --git a/chrome/browser/profiles/profiles_state.cc b/chrome/browser/profiles/profiles_state.cc
index 827c9c9..c19fb33 100644
--- a/chrome/browser/profiles/profiles_state.cc
+++ b/chrome/browser/profiles/profiles_state.cc
@@ -24,10 +24,6 @@
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/text_elider.h"
 
-#if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
-#endif
-
 namespace profiles {
 
 bool IsMultipleProfilesEnabled() {
diff --git a/chrome/browser/signin/chrome_signin_client.cc b/chrome/browser/signin/chrome_signin_client.cc
index dd909b6..66f9326 100644
--- a/chrome/browser/signin/chrome_signin_client.cc
+++ b/chrome/browser/signin/chrome_signin_client.cc
@@ -27,7 +27,7 @@
 #endif
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using content::ChildProcessHost;
@@ -116,8 +116,8 @@ scoped_refptr<TokenWebData> ChromeSigninClient::GetDatabase() {
 bool ChromeSigninClient::CanRevokeCredentials() {
 #if defined(OS_CHROMEOS)
   // UserManager may not exist in unit_tests.
-  if (chromeos::UserManager::IsInitialized() &&
-      chromeos::UserManager::Get()->IsLoggedInAsSupervisedUser()) {
+  if (user_manager::UserManager::IsInitialized() &&
+      user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser()) {
     // Don't allow revoking credentials for Chrome OS supervised users.
     // See http://crbug.com/332032
     LOG(ERROR) << "Attempt to revoke supervised user refresh "
diff --git a/chrome/browser/signin/easy_unlock_service.cc b/chrome/browser/signin/easy_unlock_service.cc
index 81d9f0e..10dbf20 100644
--- a/chrome/browser/signin/easy_unlock_service.cc
+++ b/chrome/browser/signin/easy_unlock_service.cc
@@ -25,8 +25,8 @@
 #include "grit/browser_resources.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 namespace {
@@ -91,7 +91,7 @@ void EasyUnlockService::LaunchSetup() {
 
 bool EasyUnlockService::IsAllowed() {
 #if defined(OS_CHROMEOS)
-  if (!chromeos::UserManager::Get()->IsLoggedInAsRegularUser())
+  if (!user_manager::UserManager::Get()->IsLoggedInAsRegularUser())
     return false;
 
   if (!chromeos::ProfileHelper::IsPrimaryProfile(profile_))
diff --git a/chrome/browser/signin/easy_unlock_service_browsertest_chromeos.cc b/chrome/browser/signin/easy_unlock_service_browsertest_chromeos.cc
index 577120d..44aaf56 100644
--- a/chrome/browser/signin/easy_unlock_service_browsertest_chromeos.cc
+++ b/chrome/browser/signin/easy_unlock_service_browsertest_chromeos.cc
@@ -9,7 +9,6 @@
 #include "chrome/browser/chromeos/login/login_manager_test.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/profiles/profile.h"
@@ -21,6 +20,7 @@
 #include "components/policy/core/common/mock_configuration_policy_provider.h"
 #include "components/policy/core/common/policy_map.h"
 #include "components/policy/core/common/policy_types.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/common/content_switches.h"
 #include "extensions/browser/extension_system.h"
 #include "policy/policy_constants.h"
@@ -30,7 +30,7 @@ using chromeos::ProfileHelper;
 using chromeos::LoginManagerTest;
 using chromeos::StartupUtils;
 using chromeos::UserAddingScreen;
-using chromeos::UserManager;
+using user_manager::UserManager;
 using testing::_;
 using testing::Return;
 
@@ -49,7 +49,7 @@ bool HasEasyUnlockAppForProfile(Profile* profile) {
 }
 #endif
 
-} //namespace
+}  // namespace
 
 class EasyUnlockServiceTest : public InProcessBrowserTest {
  public:
@@ -190,9 +190,9 @@ IN_PROC_BROWSER_TEST_F(EasyUnlockServiceMultiProfileTest,
   base::RunLoop().RunUntilIdle();
   AddUser(kTestUser2);
   const user_manager::User* primary_user =
-      UserManager::Get()->FindUser(kTestUser1);
+      user_manager::UserManager::Get()->FindUser(kTestUser1);
   const user_manager::User* secondary_user =
-      UserManager::Get()->FindUser(kTestUser2);
+      user_manager::UserManager::Get()->FindUser(kTestUser2);
 
   Profile* primary_profile = ProfileHelper::Get()->GetProfileByUserIdHash(
       primary_user->username_hash());
diff --git a/chrome/browser/signin/signin_error_notifier_ash.cc b/chrome/browser/signin/signin_error_notifier_ash.cc
index aae8e7c..9713889 100644
--- a/chrome/browser/signin/signin_error_notifier_ash.cc
+++ b/chrome/browser/signin/signin_error_notifier_ash.cc
@@ -35,7 +35,8 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/user_flow.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 namespace {
@@ -168,9 +169,9 @@ void SigninErrorNotifier::OnErrorChanged() {
   }
 
 #if defined(OS_CHROMEOS)
-  if (chromeos::UserManager::IsInitialized()) {
+  if (user_manager::UserManager::IsInitialized()) {
     chromeos::UserFlow* user_flow =
-        chromeos::UserManager::Get()->GetCurrentUserFlow();
+        chromeos::ChromeUserManager::Get()->GetCurrentUserFlow();
 
     // Check whether Chrome OS user flow allows launching browser.
     // Example: Supervised user creation flow which handles token invalidation
diff --git a/chrome/browser/supervised_user/chromeos/manager_password_service.cc b/chrome/browser/supervised_user/chromeos/manager_password_service.cc
index 2580d05..9c6f989 100644
--- a/chrome/browser/supervised_user/chromeos/manager_password_service.cc
+++ b/chrome/browser/supervised_user/chromeos/manager_password_service.cc
@@ -10,13 +10,14 @@
 #include "base/values.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_authentication.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_constants.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/supervised_user/supervised_user_constants.h"
 #include "chrome/browser/supervised_user/supervised_user_sync_service.h"
 #include "chromeos/login/auth/key.h"
 #include "chromeos/login/auth/user_context.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 
 namespace chromeos {
@@ -38,12 +39,11 @@ void ManagerPasswordService::Init(
 
   authenticator_ = new ExtendedAuthenticator(this);
 
-  UserManager* user_manager = UserManager::Get();
-
   SupervisedUserManager* supervised_user_manager =
-      user_manager->GetSupervisedUserManager();
+      ChromeUserManager::Get()->GetSupervisedUserManager();
 
-  const user_manager::UserList& users = user_manager->GetUsers();
+  const user_manager::UserList& users =
+      user_manager::UserManager::Get()->GetUsers();
 
   for (user_manager::UserList::const_iterator it = users.begin();
        it != users.end();
@@ -65,7 +65,7 @@ void ManagerPasswordService::OnSharedSettingsChange(
     return;
 
   SupervisedUserManager* supervised_user_manager =
-      UserManager::Get()->GetSupervisedUserManager();
+      ChromeUserManager::Get()->GetSupervisedUserManager();
   const user_manager::User* user = supervised_user_manager->FindBySyncId(su_id);
   // No user on device.
   if (user == NULL)
@@ -198,7 +198,7 @@ void ManagerPasswordService::OnAddKeySuccess(
       SupervisedUserAuthentication::PASSWORD_CHANGE_RESULT_MAX_VALUE);
 
   SupervisedUserAuthentication* auth =
-      UserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
+      ChromeUserManager::Get()->GetSupervisedUserManager()->GetAuthentication();
   int old_schema = auth->GetPasswordSchema(user_id);
   auth->StorePasswordData(user_id, *password_data.get());
 
diff --git a/chrome/browser/supervised_user/chromeos/manager_password_service_factory.cc b/chrome/browser/supervised_user/chromeos/manager_password_service_factory.cc
index 5f5df8c..3debf86 100644
--- a/chrome/browser/supervised_user/chromeos/manager_password_service_factory.cc
+++ b/chrome/browser/supervised_user/chromeos/manager_password_service_factory.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/supervised_user/chromeos/manager_password_service_factory.h"
 
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/incognito_helpers.h"
@@ -43,10 +44,9 @@ ManagerPasswordServiceFactory::
 KeyedService* ManagerPasswordServiceFactory::BuildServiceInstanceFor(
     content::BrowserContext* context) const {
   Profile* profile= static_cast<Profile*>(context);
-  user_manager::User* user =
-      chromeos::ProfileHelper::Get()->GetUserByProfile(profile);
-  if (chromeos::UserManager::Get()->GetSupervisedUserManager()->
-      HasSupervisedUsers(user->email())) {
+  user_manager::User* user = ProfileHelper::Get()->GetUserByProfile(profile);
+  if (ChromeUserManager::Get()->GetSupervisedUserManager()->HasSupervisedUsers(
+          user->email())) {
     ManagerPasswordService* result = new ManagerPasswordService();
     result->Init(
         user->email(),
diff --git a/chrome/browser/supervised_user/chromeos/supervised_user_password_service.cc b/chrome/browser/supervised_user/chromeos/supervised_user_password_service.cc
index c3dc5d0..35ae5aa 100644
--- a/chrome/browser/supervised_user/chromeos/supervised_user_password_service.cc
+++ b/chrome/browser/supervised_user/chromeos/supervised_user_password_service.cc
@@ -7,8 +7,8 @@
 #include "base/bind.h"
 #include "base/values.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_authentication.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/supervised_user/supervised_user_constants.h"
 #include "chrome/browser/supervised_user/supervised_user_sync_service.h"
 
@@ -31,7 +31,7 @@ void SupervisedUserPasswordService::Init(
   // Force value check in case we have missed some notification.
 
   chromeos::SupervisedUserManager* supervised_user_manager =
-      chromeos::UserManager::Get()->GetSupervisedUserManager();
+      ChromeUserManager::Get()->GetSupervisedUserManager();
 
   OnSharedSettingsChange(supervised_user_manager->GetUserSyncId(user_id),
                          supervised_users::kChromeOSPasswordData);
@@ -43,7 +43,7 @@ void SupervisedUserPasswordService::OnSharedSettingsChange(
   if (key != supervised_users::kChromeOSPasswordData)
     return;
   chromeos::SupervisedUserManager* supervised_user_manager =
-      chromeos::UserManager::Get()->GetSupervisedUserManager();
+      ChromeUserManager::Get()->GetSupervisedUserManager();
   const user_manager::User* user = supervised_user_manager->FindBySyncId(su_id);
   if (user == NULL) {
     LOG(WARNING) << "Got notification for user not on device.";
diff --git a/chrome/browser/supervised_user/chromeos/supervised_user_password_service_factory.cc b/chrome/browser/supervised_user/chromeos/supervised_user_password_service_factory.cc
index b210a77..370827e 100644
--- a/chrome/browser/supervised_user/chromeos/supervised_user_password_service_factory.cc
+++ b/chrome/browser/supervised_user/chromeos/supervised_user_password_service_factory.cc
@@ -5,7 +5,6 @@
 #include "chrome/browser/supervised_user/chromeos/supervised_user_password_service_factory.h"
 
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/incognito_helpers.h"
 #include "chrome/browser/profiles/profile.h"
diff --git a/chrome/browser/supervised_user/supervised_user_service.cc b/chrome/browser/supervised_user/supervised_user_service.cc
index 8b45a60..0f8cab2 100644
--- a/chrome/browser/supervised_user/supervised_user_service.cc
+++ b/chrome/browser/supervised_user/supervised_user_service.cc
@@ -47,8 +47,9 @@
 #include "ui/base/l10n/l10n_util.h"
 
 #if defined(OS_CHROMEOS)
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 #if defined(ENABLE_EXTENSIONS)
@@ -255,9 +256,10 @@ void SupervisedUserService::GetCategoryNames(CategoryList* list) {
 
 std::string SupervisedUserService::GetCustodianEmailAddress() const {
 #if defined(OS_CHROMEOS)
-  return chromeos::UserManager::Get()->GetSupervisedUserManager()->
-      GetManagerDisplayEmail(
-          chromeos::UserManager::Get()->GetActiveUser()->email());
+  return chromeos::ChromeUserManager::Get()
+      ->GetSupervisedUserManager()
+      ->GetManagerDisplayEmail(
+          user_manager::UserManager::Get()->GetActiveUser()->email());
 #else
   return profile_->GetPrefs()->GetString(prefs::kSupervisedUserCustodianEmail);
 #endif
@@ -265,9 +267,11 @@ std::string SupervisedUserService::GetCustodianEmailAddress() const {
 
 std::string SupervisedUserService::GetCustodianName() const {
 #if defined(OS_CHROMEOS)
-  return base::UTF16ToUTF8(chromeos::UserManager::Get()->
-      GetSupervisedUserManager()->GetManagerDisplayName(
-          chromeos::UserManager::Get()->GetActiveUser()->email()));
+  return base::UTF16ToUTF8(
+      chromeos::ChromeUserManager::Get()
+          ->GetSupervisedUserManager()
+          ->GetManagerDisplayName(
+              user_manager::UserManager::Get()->GetActiveUser()->email()));
 #else
   std::string name = profile_->GetPrefs()->GetString(
       prefs::kSupervisedUserCustodianName);
@@ -817,9 +821,9 @@ void SupervisedUserService::OnBrowserSetLastActive(Browser* browser) {
 std::string SupervisedUserService::GetSupervisedUserName() const {
 #if defined(OS_CHROMEOS)
   // The active user can be NULL in unit tests.
-  if (chromeos::UserManager::Get()->GetActiveUser()) {
-    return UTF16ToUTF8(chromeos::UserManager::Get()->GetUserDisplayName(
-        chromeos::UserManager::Get()->GetActiveUser()->GetUserID()));
+  if (user_manager::UserManager::Get()->GetActiveUser()) {
+    return UTF16ToUTF8(user_manager::UserManager::Get()->GetUserDisplayName(
+        user_manager::UserManager::Get()->GetActiveUser()->GetUserID()));
   }
   return std::string();
 #else
diff --git a/chrome/browser/sync/sync_error_notifier_ash.cc b/chrome/browser/sync/sync_error_notifier_ash.cc
index 473738e..f203dce 100644
--- a/chrome/browser/sync/sync_error_notifier_ash.cc
+++ b/chrome/browser/sync/sync_error_notifier_ash.cc
@@ -29,7 +29,8 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/user_flow.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 
@@ -155,9 +156,9 @@ void SyncErrorNotifier::OnErrorChanged() {
   }
 
 #if defined(OS_CHROMEOS)
-  if (chromeos::UserManager::IsInitialized()) {
+  if (user_manager::UserManager::IsInitialized()) {
     chromeos::UserFlow* user_flow =
-        chromeos::UserManager::Get()->GetCurrentUserFlow();
+        chromeos::ChromeUserManager::Get()->GetCurrentUserFlow();
 
     // Check whether Chrome OS user flow allows launching browser.
     // Example: Supervised user creation flow which handles token invalidation
diff --git a/chrome/browser/sync/sync_ui_util.cc b/chrome/browser/sync/sync_ui_util.cc
index 3a15e24..8143ca3 100644
--- a/chrome/browser/sync/sync_ui_util.cc
+++ b/chrome/browser/sync/sync_ui_util.cc
@@ -37,7 +37,7 @@
 #include "ui/base/l10n/l10n_util.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif  // defined(OS_CHROMEOS)
 
 typedef GoogleServiceAuthError AuthError;
@@ -55,11 +55,11 @@ base::string16 GetSyncedStateStatusLabel(ProfileSyncService* service,
   std::string user_display_name = signin.GetAuthenticatedUsername();
 
 #if defined(OS_CHROMEOS)
-  if (chromeos::UserManager::IsInitialized()) {
+  if (user_manager::UserManager::IsInitialized()) {
     // On CrOS user email is sanitized and then passed to the signin manager.
     // Original email (containing dots) is stored as "display email".
-    user_display_name = chromeos::UserManager::Get()->
-        GetUserDisplayEmail(user_display_name);
+    user_display_name = user_manager::UserManager::Get()->GetUserDisplayEmail(
+        user_display_name);
   }
 #endif  // defined(OS_CHROMEOS)
 
diff --git a/chrome/browser/sync_file_system/drive_backend_v1/drive_file_sync_service_fake_unittest.cc b/chrome/browser/sync_file_system/drive_backend_v1/drive_file_sync_service_fake_unittest.cc
index 02cca9e..93b55e6 100644
--- a/chrome/browser/sync_file_system/drive_backend_v1/drive_file_sync_service_fake_unittest.cc
+++ b/chrome/browser/sync_file_system/drive_backend_v1/drive_file_sync_service_fake_unittest.cc
@@ -42,7 +42,7 @@
 #include "webkit/common/fileapi/file_system_util.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/themes/theme_syncable_service_unittest.cc b/chrome/browser/themes/theme_syncable_service_unittest.cc
index 9f37de4..c671452 100644
--- a/chrome/browser/themes/theme_syncable_service_unittest.cc
+++ b/chrome/browser/themes/theme_syncable_service_unittest.cc
@@ -34,7 +34,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/ui/ash/app_sync_ui_state.cc b/chrome/browser/ui/ash/app_sync_ui_state.cc
index 78bb2b3..27d2d11 100644
--- a/chrome/browser/ui/ash/app_sync_ui_state.cc
+++ b/chrome/browser/ui/ash/app_sync_ui_state.cc
@@ -16,7 +16,7 @@
 #include "extensions/browser/extension_system.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 namespace {
@@ -34,7 +34,7 @@ AppSyncUIState* AppSyncUIState::Get(Profile* profile) {
 // static
 bool AppSyncUIState::ShouldObserveAppSyncForProfile(Profile* profile) {
 #if defined(OS_CHROMEOS)
-  if (chromeos::UserManager::Get()->IsLoggedInAsGuest())
+  if (user_manager::UserManager::Get()->IsLoggedInAsGuest())
     return false;
 
   if (!profile || profile->IsOffTheRecord())
diff --git a/chrome/browser/ui/ash/chrome_shell_delegate.cc b/chrome/browser/ui/ash/chrome_shell_delegate.cc
index d4daa66..9ac7946 100644
--- a/chrome/browser/ui/ash/chrome_shell_delegate.cc
+++ b/chrome/browser/ui/ash/chrome_shell_delegate.cc
@@ -29,7 +29,7 @@
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/accessibility/accessibility_manager.h"
 #include "chrome/browser/chromeos/display/display_configuration_observer.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 // static
@@ -52,12 +52,13 @@ bool ChromeShellDelegate::IsMultiProfilesEnabled() const {
 #if defined(OS_CHROMEOS)
   // If there is a user manager, we need to see that we can at least have 2
   // simultaneous users to allow this feature.
-  if (!chromeos::UserManager::IsInitialized())
+  if (!user_manager::UserManager::IsInitialized())
     return false;
-  size_t admitted_users_to_be_added =
-      chromeos::UserManager::Get()->GetUsersAdmittedForMultiProfile().size();
+  size_t admitted_users_to_be_added = user_manager::UserManager::Get()
+                                          ->GetUsersAdmittedForMultiProfile()
+                                          .size();
   size_t logged_in_users =
-      chromeos::UserManager::Get()->GetLoggedInUsers().size();
+      user_manager::UserManager::Get()->GetLoggedInUsers().size();
   if (!logged_in_users) {
     // The shelf gets created on the login screen and as such we have to create
     // all multi profile items of the the system tray menu before the user logs
@@ -99,7 +100,7 @@ void ChromeShellDelegate::Exit() {
 
 content::BrowserContext* ChromeShellDelegate::GetActiveBrowserContext() {
 #if defined(OS_CHROMEOS)
-  DCHECK(chromeos::UserManager::Get()->GetLoggedInUsers().size());
+  DCHECK(user_manager::UserManager::Get()->GetLoggedInUsers().size());
 #endif
   return ProfileManager::GetActiveUserProfile();
 }
diff --git a/chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc b/chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc
index 744fb2d..f6b4379 100644
--- a/chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc
+++ b/chrome/browser/ui/ash/launcher/chrome_launcher_controller.cc
@@ -91,10 +91,10 @@
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/ui/ash/chrome_shell_delegate.h"
 #include "chrome/browser/ui/ash/launcher/multi_profile_app_window_launcher_controller.h"
 #include "chrome/browser/ui/ash/launcher/multi_profile_browser_status_monitor.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using extensions::Extension;
@@ -269,14 +269,14 @@ std::string GetSourceFromAppListSource(ash::LaunchSource source) {
 // A class to get events from ChromeOS when a user gets changed or added.
 class ChromeLauncherControllerUserSwitchObserverChromeOS
     : public ChromeLauncherControllerUserSwitchObserver,
-      public chromeos::UserManager::UserSessionStateObserver,
+      public user_manager::UserManager::UserSessionStateObserver,
       content::NotificationObserver {
  public:
   ChromeLauncherControllerUserSwitchObserverChromeOS(
       ChromeLauncherController* controller)
       : controller_(controller) {
-    DCHECK(chromeos::UserManager::IsInitialized());
-    chromeos::UserManager::Get()->AddSessionStateObserver(this);
+    DCHECK(user_manager::UserManager::IsInitialized());
+    user_manager::UserManager::Get()->AddSessionStateObserver(this);
     // A UserAddedToSession notification can be sent before a profile is loaded.
     // Since our observers require that we have already a profile, we might have
     // to postpone the notification until the ProfileManager lets us know that
@@ -285,10 +285,10 @@ class ChromeLauncherControllerUserSwitchObserverChromeOS
                    content::NotificationService::AllSources());
   }
   virtual ~ChromeLauncherControllerUserSwitchObserverChromeOS() {
-    chromeos::UserManager::Get()->RemoveSessionStateObserver(this);
+    user_manager::UserManager::Get()->RemoveSessionStateObserver(this);
   }
 
-  // chromeos::UserManager::UserSessionStateObserver overrides:
+  // user_manager::UserManager::UserSessionStateObserver overrides:
   virtual void UserAddedToSession(
       const user_manager::User* added_user) OVERRIDE;
 
diff --git a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_unittest.cc b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_unittest.cc
index 65946a3..b9ae930 100644
--- a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_unittest.cc
+++ b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_unittest.cc
@@ -53,6 +53,7 @@
 #include "ash/test/test_session_state_delegate.h"
 #include "ash/test/test_shell_delegate.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/ui/apps/chrome_app_delegate.h"
 #include "chrome/browser/ui/ash/launcher/app_window_launcher_controller.h"
 #include "chrome/browser/ui/ash/launcher/browser_status_monitor.h"
@@ -925,7 +926,7 @@ class MultiProfileMultiBrowserShelfLayoutChromeLauncherControllerTest
 
   chromeos::FakeUserManager* GetFakeUserManager() {
     return static_cast<chromeos::FakeUserManager*>(
-        chromeos::UserManager::Get());
+        user_manager::UserManager::Get());
   }
 
   scoped_ptr<TestingProfileManager> profile_manager_;
diff --git a/chrome/browser/ui/ash/multi_user/multi_user_context_menu_chromeos.cc b/chrome/browser/ui/ash/multi_user/multi_user_context_menu_chromeos.cc
index d2a61b2..f9100aa 100644
--- a/chrome/browser/ui/ash/multi_user/multi_user_context_menu_chromeos.cc
+++ b/chrome/browser/ui/ash/multi_user/multi_user_context_menu_chromeos.cc
@@ -12,7 +12,6 @@
 #include "base/prefs/pref_service.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/app/chrome_command_ids.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/ui/ash/multi_user/multi_user_util.h"
@@ -20,6 +19,7 @@
 #include "chrome/browser/ui/ash/multi_user/multi_user_window_manager.h"
 #include "chrome/common/pref_names.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "grit/generated_resources.h"
 #include "ui/aura/window.h"
 #include "ui/base/l10n/l10n_util.h"
@@ -130,7 +130,7 @@ void ExecuteVisitDesktopCommand(int command_id, aura::Window* window) {
       // Don't show warning dialog if any logged in user in multi-profiles
       // session dismissed it.
       const user_manager::UserList logged_in_users =
-          chromeos::UserManager::Get()->GetLoggedInUsers();
+          user_manager::UserManager::Get()->GetLoggedInUsers();
       for (user_manager::UserList::const_iterator it = logged_in_users.begin();
            it != logged_in_users.end();
            ++it) {
diff --git a/chrome/browser/ui/ash/multi_user/multi_user_util.cc b/chrome/browser/ui/ash/multi_user/multi_user_util.cc
index 9aecd93..749e29b 100644
--- a/chrome/browser/ui/ash/multi_user/multi_user_util.cc
+++ b/chrome/browser/ui/ash/multi_user/multi_user_util.cc
@@ -13,8 +13,8 @@
 #include "google_apis/gaia/gaia_auth_util.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/ui/ash/multi_user/multi_user_window_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 namespace multi_user_util {
@@ -63,7 +63,7 @@ Profile* GetProfileFromWindow(aura::Window* window) {
 bool IsProfileFromActiveUser(Profile* profile) {
 #if defined(OS_CHROMEOS)
   return GetUserIDFromProfile(profile) ==
-         chromeos::UserManager::Get()->GetActiveUser()->email();
+         user_manager::UserManager::Get()->GetActiveUser()->email();
 #else
   // In non Chrome OS configurations this will be always true since this only
   // makes sense in separate desktop mode.
@@ -73,7 +73,7 @@ bool IsProfileFromActiveUser(Profile* profile) {
 
 const std::string& GetCurrentUserId() {
 #if defined(OS_CHROMEOS)
-  return chromeos::UserManager::Get()->GetActiveUser()->email();
+  return user_manager::UserManager::Get()->GetActiveUser()->email();
 #else
   return base::EmptyString();
 #endif
diff --git a/chrome/browser/ui/ash/multi_user/multi_user_window_manager_chromeos.cc b/chrome/browser/ui/ash/multi_user/multi_user_window_manager_chromeos.cc
index 126a469..097559d 100644
--- a/chrome/browser/ui/ash/multi_user/multi_user_window_manager_chromeos.cc
+++ b/chrome/browser/ui/ash/multi_user/multi_user_window_manager_chromeos.cc
@@ -22,7 +22,6 @@
 #include "base/strings/string_util.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/ui/ash/multi_user/multi_user_notification_blocker_chromeos.h"
diff --git a/chrome/browser/ui/ash/screenshot_taker.cc b/chrome/browser/ui/ash/screenshot_taker.cc
index 4cee448..d8fe27e 100644
--- a/chrome/browser/ui/ash/screenshot_taker.cc
+++ b/chrome/browser/ui/ash/screenshot_taker.cc
@@ -45,7 +45,6 @@
 #include "chrome/browser/chromeos/drive/file_system_interface.h"
 #include "chrome/browser/chromeos/drive/file_system_util.h"
 #include "chrome/browser/chromeos/file_manager/open_util.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/notifications/desktop_notification_service.h"
 #include "chrome/browser/notifications/desktop_notification_service_factory.h"
 #include "chromeos/login/login_state.h"
diff --git a/chrome/browser/ui/ash/session_state_delegate_chromeos.cc b/chrome/browser/ui/ash/session_state_delegate_chromeos.cc
index ef9f807..2f7c840 100644
--- a/chrome/browser/ui/ash/session_state_delegate_chromeos.cc
+++ b/chrome/browser/ui/ash/session_state_delegate_chromeos.cc
@@ -12,7 +12,6 @@
 #include "chrome/browser/chromeos/login/lock/screen_locker.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
 #include "chrome/browser/chromeos/login/users/multi_profile_user_controller.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
@@ -23,11 +22,12 @@
 #include "chromeos/dbus/session_manager_client.h"
 #include "chromeos/login/login_state.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 
 SessionStateDelegateChromeos::SessionStateDelegateChromeos()
     : session_state_(SESSION_STATE_LOGIN_PRIMARY) {
-  chromeos::UserManager::Get()->AddSessionStateObserver(this);
+  user_manager::UserManager::Get()->AddSessionStateObserver(this);
   chromeos::UserAddingScreen::Get()->AddObserver(this);
 
   // LoginState is not initialized in unit_tests.
@@ -39,7 +39,7 @@ SessionStateDelegateChromeos::SessionStateDelegateChromeos()
 }
 
 SessionStateDelegateChromeos::~SessionStateDelegateChromeos() {
-  chromeos::UserManager::Get()->RemoveSessionStateObserver(this);
+  user_manager::UserManager::Get()->RemoveSessionStateObserver(this);
   chromeos::UserAddingScreen::Get()->RemoveObserver(this);
 
   // LoginState is not initialized in unit_tests.
@@ -51,7 +51,7 @@ content::BrowserContext* SessionStateDelegateChromeos::GetBrowserContextByIndex(
     ash::MultiProfileIndex index) {
   DCHECK_LT(index, NumberOfLoggedInUsers());
   user_manager::User* user =
-      chromeos::UserManager::Get()->GetLRULoggedInUsers()[index];
+      user_manager::UserManager::Get()->GetLRULoggedInUsers()[index];
   DCHECK(user);
   return chromeos::ProfileHelper::Get()->GetProfileByUserUnsafe(user);
 }
@@ -62,7 +62,7 @@ SessionStateDelegateChromeos::GetBrowserContextForWindow(
   const std::string& user_id =
       chrome::MultiUserWindowManager::GetInstance()->GetWindowOwner(window);
   const user_manager::User* user =
-      chromeos::UserManager::Get()->FindUser(user_id);
+      user_manager::UserManager::Get()->FindUser(user_id);
   DCHECK(user);
   return chromeos::ProfileHelper::Get()->GetProfileByUserUnsafe(user);
 }
@@ -77,16 +77,16 @@ int SessionStateDelegateChromeos::GetMaximumNumberOfLoggedInUsers() const {
 }
 
 int SessionStateDelegateChromeos::NumberOfLoggedInUsers() const {
-  return chromeos::UserManager::Get()->GetLoggedInUsers().size();
+  return user_manager::UserManager::Get()->GetLoggedInUsers().size();
 }
 
 bool SessionStateDelegateChromeos::IsActiveUserSessionStarted() const {
-  return chromeos::UserManager::Get()->IsSessionStarted();
+  return user_manager::UserManager::Get()->IsSessionStarted();
 }
 
 bool SessionStateDelegateChromeos::CanLockScreen() const {
   const user_manager::UserList unlock_users =
-      chromeos::UserManager::Get()->GetUnlockUsers();
+      user_manager::UserManager::Get()->GetUnlockUsers();
   return !unlock_users.empty();
 }
 
@@ -97,7 +97,7 @@ bool SessionStateDelegateChromeos::IsScreenLocked() const {
 
 bool SessionStateDelegateChromeos::ShouldLockScreenBeforeSuspending() const {
   const user_manager::UserList logged_in_users =
-      chromeos::UserManager::Get()->GetLoggedInUsers();
+      user_manager::UserManager::Get()->GetLoggedInUsers();
   for (user_manager::UserList::const_iterator it = logged_in_users.begin();
        it != logged_in_users.end();
        ++it) {
@@ -140,7 +140,7 @@ SessionStateDelegateChromeos::GetSessionState() const {
 const user_manager::UserInfo* SessionStateDelegateChromeos::GetUserInfo(
     ash::MultiProfileIndex index) const {
   DCHECK_LT(index, NumberOfLoggedInUsers());
-  return chromeos::UserManager::Get()->GetLRULoggedInUsers()[index];
+  return user_manager::UserManager::Get()->GetLRULoggedInUsers()[index];
 }
 
 const user_manager::UserInfo* SessionStateDelegateChromeos::GetUserInfo(
@@ -162,9 +162,9 @@ void SessionStateDelegateChromeos::SwitchActiveUser(
   // Also check that we got a user id and not an email address.
   DCHECK_EQ(user_id,
             gaia::CanonicalizeEmail(gaia::SanitizeEmail(user_id)));
-  if (user_id == chromeos::UserManager::Get()->GetActiveUser()->email())
+  if (user_id == user_manager::UserManager::Get()->GetActiveUser()->email())
     return;
-  chromeos::UserManager::Get()->SwitchActiveUser(user_id);
+  user_manager::UserManager::Get()->SwitchActiveUser(user_id);
 }
 
 void SessionStateDelegateChromeos::CycleActiveUser(CycleUser cycle_user) {
@@ -173,9 +173,10 @@ void SessionStateDelegateChromeos::CycleActiveUser(CycleUser cycle_user) {
     return;
 
   const user_manager::UserList& logged_in_users =
-      chromeos::UserManager::Get()->GetLoggedInUsers();
+      user_manager::UserManager::Get()->GetLoggedInUsers();
 
-  std::string user_id = chromeos::UserManager::Get()->GetActiveUser()->email();
+  std::string user_id =
+      user_manager::UserManager::Get()->GetActiveUser()->email();
 
   // Get an iterator positioned at the active user.
   user_manager::UserList::const_iterator it;
@@ -206,7 +207,7 @@ void SessionStateDelegateChromeos::CycleActiveUser(CycleUser cycle_user) {
   }
 
   // Switch using the transformed |user_id|.
-  chromeos::UserManager::Get()->SwitchActiveUser(user_id);
+  user_manager::UserManager::Get()->SwitchActiveUser(user_id);
 }
 
 bool SessionStateDelegateChromeos::IsMultiProfileAllowedByPrimaryUserPolicy()
diff --git a/chrome/browser/ui/ash/session_state_delegate_chromeos.h b/chrome/browser/ui/ash/session_state_delegate_chromeos.h
index 93f9b7da..3f9d2af 100644
--- a/chrome/browser/ui/ash/session_state_delegate_chromeos.h
+++ b/chrome/browser/ui/ash/session_state_delegate_chromeos.h
@@ -10,8 +10,8 @@
 #include "base/compiler_specific.h"
 #include "base/observer_list.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chromeos/login/login_state.h"
+#include "components/user_manager/user_manager.h"
 
 namespace ash {
 class SessionStateObserver;
@@ -20,7 +20,7 @@ class SessionStateObserver;
 class SessionStateDelegateChromeos
     : public ash::SessionStateDelegate,
       public chromeos::LoginState::Observer,
-      public chromeos::UserManager::UserSessionStateObserver,
+      public user_manager::UserManager::UserSessionStateObserver,
       public chromeos::UserAddingScreen::Observer {
  public:
   SessionStateDelegateChromeos();
@@ -57,7 +57,7 @@ class SessionStateDelegateChromeos
   // chromeos::LoginState::Observer overrides.
   virtual void LoggedInStateChanged() OVERRIDE;
 
-  // chromeos::UserManager::UserSessionStateObserver:
+  // user_manager::UserManager::UserSessionStateObserver:
   virtual void ActiveUserChanged(
       const user_manager::User* active_user) OVERRIDE;
   virtual void UserAddedToSession(
diff --git a/chrome/browser/ui/ash/session_state_delegate_chromeos_unittest.cc b/chrome/browser/ui/ash/session_state_delegate_chromeos_unittest.cc
index 2bf05dd..ec1fff7 100644
--- a/chrome/browser/ui/ash/session_state_delegate_chromeos_unittest.cc
+++ b/chrome/browser/ui/ash/session_state_delegate_chromeos_unittest.cc
@@ -10,6 +10,7 @@
 #include "base/run_loop.h"
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
 #include "chrome/browser/chromeos/login/users/multi_profile_user_controller.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/chromeos/policy/policy_cert_service.h"
 #include "chrome/browser/chromeos/policy/policy_cert_service_factory.h"
 #include "chrome/browser/chromeos/policy/policy_cert_verifier.h"
@@ -17,6 +18,7 @@
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_browser_process.h"
 #include "chrome/test/base/testing_profile_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/test/test_browser_thread_bundle.h"
 #include "net/cert/x509_certificate.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -35,7 +37,7 @@ KeyedService* CreateTestPolicyCertService(content::BrowserContext* context) {
   return policy::PolicyCertService::CreateForTesting(
              kUser,
              g_policy_cert_verifier_for_factory,
-             chromeos::UserManager::Get()).release();
+             user_manager::UserManager::Get()).release();
 }
 
 }  // namespace
@@ -85,7 +87,7 @@ class SessionStateDelegateChromeOSTest : public testing::Test {
 
   // Get the active user.
   const std::string& GetActiveUser() {
-    return chromeos::UserManager::Get()->GetActiveUser()->email();
+    return user_manager::UserManager::Get()->GetActiveUser()->email();
   }
 
   chromeos::FakeUserManager* user_manager() { return user_manager_; }
diff --git a/chrome/browser/ui/ash/system_tray_delegate_chromeos.cc b/chrome/browser/ui/ash/system_tray_delegate_chromeos.cc
index 3c260d5..4c98092 100644
--- a/chrome/browser/ui/ash/system_tray_delegate_chromeos.cc
+++ b/chrome/browser/ui/ash/system_tray_delegate_chromeos.cc
@@ -56,8 +56,9 @@
 #include "chrome/browser/chromeos/login/ui/login_display_host.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
+#include "chrome/browser/chromeos/login/user_flow.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/options/network_config_view.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_cloud_policy_manager_chromeos.h"
@@ -96,6 +97,7 @@
 #include "components/google/core/browser/google_util.h"
 #include "components/policy/core/common/cloud/cloud_policy_store.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_service.h"
@@ -375,16 +377,20 @@ const base::string16 SystemTrayDelegateChromeOS::GetEnterpriseMessage() const {
 const std::string SystemTrayDelegateChromeOS::GetSupervisedUserManager() const {
   if (GetUserLoginStatus() != ash::user::LOGGED_IN_SUPERVISED)
     return std::string();
-  return UserManager::Get()->GetSupervisedUserManager()->GetManagerDisplayEmail(
-      chromeos::UserManager::Get()->GetActiveUser()->email());
+  return ChromeUserManager::Get()
+      ->GetSupervisedUserManager()
+      ->GetManagerDisplayEmail(
+          user_manager::UserManager::Get()->GetActiveUser()->email());
 }
 
 const base::string16
 SystemTrayDelegateChromeOS::GetSupervisedUserManagerName() const {
   if (GetUserLoginStatus() != ash::user::LOGGED_IN_SUPERVISED)
     return base::string16();
-  return UserManager::Get()->GetSupervisedUserManager()->GetManagerDisplayName(
-      chromeos::UserManager::Get()->GetActiveUser()->email());
+  return ChromeUserManager::Get()
+      ->GetSupervisedUserManager()
+      ->GetManagerDisplayName(
+          user_manager::UserManager::Get()->GetActiveUser()->email());
 }
 
 const base::string16 SystemTrayDelegateChromeOS::GetSupervisedUserMessage()
@@ -409,7 +415,7 @@ void SystemTrayDelegateChromeOS::ShowSettings() {
 }
 
 bool SystemTrayDelegateChromeOS::ShouldShowSettings() {
-  return UserManager::Get()->GetCurrentUserFlow()->ShouldShowSettings() &&
+  return ChromeUserManager::Get()->GetCurrentUserFlow()->ShouldShowSettings() &&
          !ash::Shell::GetInstance()
               ->session_state_delegate()
               ->IsInSecondaryLoginScreen();
@@ -538,22 +544,25 @@ void SystemTrayDelegateChromeOS::ShowUserLogin() {
     return;
 
   // Only regular users could add other users to current session.
-  if (UserManager::Get()->GetActiveUser()->GetType() !=
+  if (user_manager::UserManager::Get()->GetActiveUser()->GetType() !=
       user_manager::USER_TYPE_REGULAR) {
     return;
   }
 
-  if (static_cast<int>(UserManager::Get()->GetLoggedInUsers().size()) >=
+  if (static_cast<int>(
+          user_manager::UserManager::Get()->GetLoggedInUsers().size()) >=
       shell->session_state_delegate()->GetMaximumNumberOfLoggedInUsers())
     return;
 
   // Launch sign in screen to add another user to current session.
-  if (UserManager::Get()->GetUsersAdmittedForMultiProfile().size()) {
+  if (user_manager::UserManager::Get()
+          ->GetUsersAdmittedForMultiProfile()
+          .size()) {
     // Don't show dialog if any logged in user in multi-profiles session
     // dismissed it.
     bool show_intro = true;
     const user_manager::UserList logged_in_users =
-        UserManager::Get()->GetLoggedInUsers();
+        user_manager::UserManager::Get()->GetLoggedInUsers();
     for (user_manager::UserList::const_iterator it = logged_in_users.begin();
          it != logged_in_users.end();
          ++it) {
@@ -830,7 +839,8 @@ ash::tray::UserAccountsDelegate*
 SystemTrayDelegateChromeOS::GetUserAccountsDelegate(
     const std::string& user_id) {
   if (!accounts_delegates_.contains(user_id)) {
-    const user_manager::User* user = UserManager::Get()->FindUser(user_id);
+    const user_manager::User* user =
+        user_manager::UserManager::Get()->FindUser(user_id);
     Profile* user_profile = ProfileHelper::Get()->GetProfileByUserUnsafe(user);
     CHECK(user_profile);
     accounts_delegates_.set(
@@ -949,7 +959,7 @@ void SystemTrayDelegateChromeOS::UpdateClockType() {
   GetSystemTrayNotifier()->NotifyDateFormatChanged();
   // This also works for enterprise-managed devices because they never have
   // local owner.
-  if (chromeos::UserManager::Get()->IsCurrentUserOwner())
+  if (user_manager::UserManager::Get()->IsCurrentUserOwner())
     CrosSettings::Get()->SetBoolean(kSystemUse24HourClock, use_24_hour_clock);
 }
 
@@ -1039,7 +1049,7 @@ void SystemTrayDelegateChromeOS::LoggedInStateChanged() {
   // method, as LoggedInStateChanged() is also called before the logged-in
   // user's profile has actually been loaded (http://crbug.com/317745). The
   // system tray's time format is updated at login via SetProfile().
-  if (chromeos::UserManager::Get()->IsCurrentUserOwner()) {
+  if (user_manager::UserManager::Get()->IsCurrentUserOwner()) {
     CrosSettings::Get()->SetBoolean(kSystemUse24HourClock,
                                     ShouldUse24HourClock());
   }
diff --git a/chrome/browser/ui/ash/user_accounts_delegate_chromeos.cc b/chrome/browser/ui/ash/user_accounts_delegate_chromeos.cc
index 13aa115..f71dc0e 100644
--- a/chrome/browser/ui/ash/user_accounts_delegate_chromeos.cc
+++ b/chrome/browser/ui/ash/user_accounts_delegate_chromeos.cc
@@ -8,7 +8,6 @@
 #include <iterator>
 
 #include "base/logging.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/ui/inline_login_dialog.h"
 #include "chrome/browser/signin/profile_oauth2_token_service_factory.h"
@@ -16,6 +15,7 @@
 #include "components/signin/core/browser/mutable_profile_oauth2_token_service.h"
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
 #include "components/signin/core/browser/signin_manager.h"
+#include "components/user_manager/user.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 
 namespace chromeos {
diff --git a/chrome/browser/ui/browser_list.cc b/chrome/browser/ui/browser_list.cc
index d0dc338..000c4c6 100644
--- a/chrome/browser/ui/browser_list.cc
+++ b/chrome/browser/ui/browser_list.cc
@@ -21,10 +21,6 @@
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/user_metrics.h"
 
-#if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
-#endif
-
 using base::UserMetricsAction;
 using content::WebContents;
 
diff --git a/chrome/browser/ui/location_bar/origin_chip_info_unittest.cc b/chrome/browser/ui/location_bar/origin_chip_info_unittest.cc
index 496da58..9257308 100644
--- a/chrome/browser/ui/location_bar/origin_chip_info_unittest.cc
+++ b/chrome/browser/ui/location_bar/origin_chip_info_unittest.cc
@@ -21,7 +21,7 @@
 #include "ui/base/l10n/l10n_util.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/ui/startup/startup_browser_creator.cc b/chrome/browser/ui/startup/startup_browser_creator.cc
index fd046f8..63de334 100644
--- a/chrome/browser/ui/startup/startup_browser_creator.cc
+++ b/chrome/browser/ui/startup/startup_browser_creator.cc
@@ -73,10 +73,10 @@
 #include "chrome/browser/chromeos/app_mode/app_launch_utils.h"
 #include "chrome/browser/chromeos/kiosk_mode/kiosk_mode_settings.h"
 #include "chrome/browser/chromeos/login/demo_mode/demo_app_launcher.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chromeos/chromeos_switches.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 #if defined(TOOLKIT_VIEWS) && defined(OS_LINUX)
@@ -359,7 +359,8 @@ SessionStartupPref StartupBrowserCreator::GetSessionStartupPref(
   // in a location shared by all users and the check is meaningless. Query the
   // UserManager instead to determine whether the user is new.
 #if defined(OS_CHROMEOS)
-  const bool is_first_run = chromeos::UserManager::Get()->IsCurrentUserNew();
+  const bool is_first_run =
+      user_manager::UserManager::Get()->IsCurrentUserNew();
 #else
   const bool is_first_run = first_run::IsChromeFirstRun();
 #endif
diff --git a/chrome/browser/ui/sync/profile_signin_confirmation_helper_unittest.cc b/chrome/browser/ui/sync/profile_signin_confirmation_helper_unittest.cc
index 2bed91c..68bc2e1 100644
--- a/chrome/browser/ui/sync/profile_signin_confirmation_helper_unittest.cc
+++ b/chrome/browser/ui/sync/profile_signin_confirmation_helper_unittest.cc
@@ -34,7 +34,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/chrome/browser/ui/webui/chromeos/first_run/first_run_ui.cc b/chrome/browser/ui/webui/chromeos/first_run/first_run_ui.cc
index 0ac74e6..d2828dd 100644
--- a/chrome/browser/ui/webui/chromeos/first_run/first_run_ui.cc
+++ b/chrome/browser/ui/webui/chromeos/first_run/first_run_ui.cc
@@ -6,7 +6,6 @@
 
 #include "ash/shell.h"
 #include "base/command_line.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/webui/chromeos/first_run/first_run_handler.h"
 #include "chrome/common/url_constants.h"
diff --git a/chrome/browser/ui/webui/chromeos/login/error_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/error_screen_handler.cc
index e15ba2d..5a6a77a 100644
--- a/chrome/browser/ui/webui/chromeos/login/error_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/error_screen_handler.cc
@@ -23,6 +23,7 @@
 #include "chromeos/dbus/session_manager_client.h"
 #include "chromeos/network/portal_detector/network_portal_detector.h"
 #include "chromeos/network/portal_detector/network_portal_detector_strategy.h"
+#include "components/user_manager/user_manager.h"
 #include "extensions/browser/extension_system.h"
 #include "grit/browser_resources.h"
 #include "grit/chromium_strings.h"
@@ -204,7 +205,7 @@ void ErrorScreenHandler::HandleDiagnoseButtonClicked() {
                                   NEW_WINDOW));
   InitAppSession(profile, extension_id);
 
-  UserManager::Get()->SessionStarted();
+  user_manager::UserManager::Get()->SessionStarted();
 
   LoginDisplayHostImpl::default_host()->Finalize();
 }
diff --git a/chrome/browser/ui/webui/chromeos/login/gaia_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/gaia_screen_handler.cc
index b66ae6a..7e84e9d 100644
--- a/chrome/browser/ui/webui/chromeos/login/gaia_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/gaia_screen_handler.cc
@@ -12,7 +12,6 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_shutdown.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/consumer_management_service.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
@@ -21,6 +20,7 @@
 #include "chrome/browser/ui/webui/signin/inline_login_ui.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/settings/cros_settings_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_frame_host.h"
 #include "google_apis/gaia/gaia_auth_util.h"
@@ -59,7 +59,7 @@ void UpdateAuthParams(base::DictionaryValue* params,
   // 3. New users are allowed by owner.
   // 4. Supervised users are allowed by owner.
   bool supervised_users_allowed =
-      UserManager::Get()->AreSupervisedUsersAllowed();
+      user_manager::UserManager::Get()->AreSupervisedUsersAllowed();
   bool supervised_users_can_create = true;
   int message_id = -1;
   if (!has_users) {
@@ -306,7 +306,8 @@ void GaiaScreenHandler::HandleCompleteLogin(const std::string& typed_email,
   }
 
   // Consumer management enrollment is in progress.
-  const std::string owner_email = UserManager::Get()->GetOwnerEmail();
+  const std::string owner_email =
+      user_manager::UserManager::Get()->GetOwnerEmail();
   if (typed_email != owner_email) {
     // Show Gaia sign-in screen again, since we only allow the owner to sign
     // in.
diff --git a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
index b88861d..138e06f 100644
--- a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
@@ -36,7 +36,6 @@
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 #include "chrome/browser/chromeos/login/ui/webui_login_display.h"
 #include "chrome/browser/chromeos/login/users/multi_profile_user_controller.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
@@ -66,6 +65,7 @@
 #include "chromeos/network/network_state_handler.h"
 #include "chromeos/network/portal_detector/network_portal_detector.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
@@ -974,7 +974,7 @@ bool SigninScreenHandler::ShouldLoadGaia() const {
 
 // Update keyboard layout to least recently used by the user.
 void SigninScreenHandler::SetUserInputMethod(const std::string& username) {
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   if (user_manager->IsUserLoggedIn()) {
     // We are on sign-in screen inside user session (adding new user to
     // the session or on lock screen), don't switch input methods in this case.
@@ -1059,7 +1059,7 @@ void SigninScreenHandler::HandleLaunchIncognito() {
 }
 
 void SigninScreenHandler::HandleShowSupervisedUserCreationScreen() {
-  if (!UserManager::Get()->AreSupervisedUsersAllowed()) {
+  if (!user_manager::UserManager::Get()->AreSupervisedUsersAllowed()) {
     LOG(ERROR) << "Managed users not allowed.";
     return;
   }
@@ -1284,7 +1284,7 @@ void SigninScreenHandler::HandleLoginUIStateChanged(const std::string& source,
 }
 
 void SigninScreenHandler::HandleUnlockOnLoginSuccess() {
-  DCHECK(UserManager::Get()->IsUserLoggedIn());
+  DCHECK(user_manager::UserManager::Get()->IsUserLoggedIn());
   if (ScreenLocker::default_screen_locker())
     ScreenLocker::default_screen_locker()->UnlockOnLoginSuccess();
 }
@@ -1360,7 +1360,7 @@ bool SigninScreenHandler::AllWhitelistedUsersPresent() {
   cros_settings->GetBoolean(kAccountsPrefAllowNewUser, &allow_new_user);
   if (allow_new_user)
     return false;
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   const user_manager::UserList& users = user_manager->GetUsers();
   if (!delegate_ || users.size() > kMaxUsers) {
     return false;
diff --git a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h
index 2d8ffab..86d4dda 100644
--- a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h
+++ b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h
@@ -20,7 +20,6 @@
 #include "chrome/browser/chromeos/login/screens/error_screen_actor.h"
 #include "chrome/browser/chromeos/login/signin_specifics.h"
 #include "chrome/browser/chromeos/login/ui/login_display.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/signin/screenlock_bridge.h"
 #include "chrome/browser/ui/webui/chromeos/login/base_screen_handler.h"
@@ -29,6 +28,7 @@
 #include "chrome/browser/ui/webui/chromeos/login/oobe_ui.h"
 #include "chromeos/ime/ime_keyboard.h"
 #include "chromeos/network/portal_detector/network_portal_detector.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/web_ui.h"
diff --git a/chrome/browser/ui/webui/chromeos/login/signin_userlist_unittest.cc b/chrome/browser/ui/webui/chromeos/login/signin_userlist_unittest.cc
index 0aa3dea..7264143 100644
--- a/chrome/browser/ui/webui/chromeos/login/signin_userlist_unittest.cc
+++ b/chrome/browser/ui/webui/chromeos/login/signin_userlist_unittest.cc
@@ -7,6 +7,7 @@
 #include "chrome/browser/chromeos/login/users/fake_user_manager.h"
 #include "chrome/browser/chromeos/login/users/multi_profile_user_controller.h"
 #include "chrome/browser/chromeos/login/users/multi_profile_user_controller_delegate.h"
+#include "chrome/browser/chromeos/login/users/scoped_user_manager_enabler.h"
 #include "chrome/browser/signin/screenlock_bridge.h"
 #include "chrome/test/base/testing_browser_process.h"
 #include "chrome/test/base/testing_profile_manager.h"
diff --git a/chrome/browser/ui/webui/chromeos/login/supervised_user_creation_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/supervised_user_creation_screen_handler.cc
index c448b7e..e9ef462 100644
--- a/chrome/browser/ui/webui/chromeos/login/supervised_user_creation_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/supervised_user_creation_screen_handler.cc
@@ -9,13 +9,14 @@
 #include "base/values.h"
 #include "chrome/browser/chromeos/login/screens/user_selection_screen.h"
 #include "chrome/browser/chromeos/login/supervised/supervised_user_creation_flow.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/login/users/supervised_user_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/ui/webui/chromeos/login/oobe_ui.h"
 #include "chrome/common/url_constants.h"
 #include "chromeos/audio/chromeos_sounds.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 #include "grit/browser_resources.h"
@@ -209,7 +210,8 @@ void SupervisedUserCreationScreenHandler::PrepareToShow() {}
 void SupervisedUserCreationScreenHandler::Show() {
   scoped_ptr<base::DictionaryValue> data(new base::DictionaryValue());
   scoped_ptr<base::ListValue> users_list(new base::ListValue());
-  const user_manager::UserList& users = UserManager::Get()->GetUsers();
+  const user_manager::UserList& users =
+      user_manager::UserManager::Get()->GetUsers();
   std::string owner;
   chromeos::CrosSettings::Get()->GetString(chromeos::kDeviceOwner, &owner);
 
@@ -301,8 +303,9 @@ void SupervisedUserCreationScreenHandler::HandleImportUserSelected(
 void SupervisedUserCreationScreenHandler::HandleCheckSupervisedUserName(
     const base::string16& name) {
   std::string user_id;
-  if (NULL != UserManager::Get()->GetSupervisedUserManager()->
-          FindByDisplayName(base::CollapseWhitespace(name, true))) {
+  if (NULL !=
+      ChromeUserManager::Get()->GetSupervisedUserManager()->FindByDisplayName(
+          base::CollapseWhitespace(name, true))) {
     CallJS("supervisedUserNameError", name,
            l10n_util::GetStringUTF16(
                IDS_CREATE_SUPERVISED_USER_CREATE_USERNAME_ALREADY_EXISTS));
@@ -325,8 +328,9 @@ void SupervisedUserCreationScreenHandler::HandleCreateSupervisedUser(
     return;
   const base::string16 new_user_name =
       base::CollapseWhitespace(new_raw_user_name, true);
-  if (NULL != UserManager::Get()->GetSupervisedUserManager()->
-          FindByDisplayName(new_user_name)) {
+  if (NULL !=
+      ChromeUserManager::Get()->GetSupervisedUserManager()->FindByDisplayName(
+          new_user_name)) {
     CallJS("supervisedUserNameError", new_user_name,
            l10n_util::GetStringFUTF16(
                IDS_CREATE_SUPERVISED_USER_CREATE_USERNAME_ALREADY_EXISTS,
@@ -384,7 +388,7 @@ void SupervisedUserCreationScreenHandler::HandleAuthenticateManager(
       gaia::SanitizeEmail(raw_manager_username);
 
   UserFlow* flow = new SupervisedUserCreationFlow(manager_username);
-  UserManager::Get()->SetUserFlow(manager_username, flow);
+  ChromeUserManager::Get()->SetUserFlow(manager_username, flow);
 
   delegate_->AuthenticateManager(manager_username, manager_password);
 }
diff --git a/chrome/browser/ui/webui/chromeos/login/terms_of_service_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/terms_of_service_screen_handler.cc
index 8bf0287..898827b 100644
--- a/chrome/browser/ui/webui/chromeos/login/terms_of_service_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/terms_of_service_screen_handler.cc
@@ -15,13 +15,14 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/base/locale_util.h"
 #include "chrome/browser/chromeos/login/screens/core_oobe_actor.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/ui/webui/chromeos/login/oobe_ui.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/ime/input_method_manager.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/web_ui.h"
 #include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
@@ -84,9 +85,11 @@ void TermsOfServiceScreenHandler::Show() {
 
   const std::string locale =
       ProfileHelper::Get()
-          ->GetProfileByUserUnsafe(UserManager::Get()->GetActiveUser())
+          ->GetProfileByUserUnsafe(
+              user_manager::UserManager::Get()->GetActiveUser())
           ->GetPrefs()
           ->GetString(prefs::kApplicationLocale);
+
   if (locale.empty() || locale == g_browser_process->GetApplicationLocale()) {
     // If the user has not chosen a UI locale yet or the chosen locale matches
     // the current UI locale, show the screen immediately.
@@ -151,7 +154,8 @@ void TermsOfServiceScreenHandler::DoShow() {
   std::vector<std::string> input_methods;
   base::SplitString(
       ProfileHelper::Get()
-          ->GetProfileByUserUnsafe(UserManager::Get()->GetActiveUser())
+          ->GetProfileByUserUnsafe(
+              user_manager::UserManager::Get()->GetActiveUser())
           ->GetPrefs()
           ->GetString(prefs::kLanguagePreloadEngines),
       ',',
diff --git a/chrome/browser/ui/webui/chromeos/ui_account_tweaks.cc b/chrome/browser/ui/webui/chromeos/ui_account_tweaks.cc
index 3257cb4..3e1727b 100644
--- a/chrome/browser/ui/webui/chromeos/ui_account_tweaks.cc
+++ b/chrome/browser/ui/webui/chromeos/ui_account_tweaks.cc
@@ -6,10 +6,10 @@
 
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chromeos/settings/cros_settings_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/web_ui_data_source.h"
 
 namespace chromeos {
@@ -23,20 +23,22 @@ void AddAccountUITweaksLocalizedValues(
   CrosSettings::Get()->GetString(kDeviceOwner, &owner_email);
   // Translate owner's email to the display email.
   std::string display_email =
-      UserManager::Get()->GetUserDisplayEmail(owner_email);
+      user_manager::UserManager::Get()->GetUserDisplayEmail(owner_email);
   localized_strings->SetString("ownerUserId", display_email);
 
   localized_strings->SetBoolean("currentUserIsOwner",
       ProfileHelper::IsOwnerProfile(profile));
 
-  localized_strings->SetBoolean("loggedInAsGuest",
-      UserManager::Get()->IsLoggedInAsGuest());
+  localized_strings->SetBoolean(
+      "loggedInAsGuest", user_manager::UserManager::Get()->IsLoggedInAsGuest());
 
-  localized_strings->SetBoolean("loggedInAsSupervisedUser",
-      UserManager::Get()->IsLoggedInAsSupervisedUser());
+  localized_strings->SetBoolean(
+      "loggedInAsSupervisedUser",
+      user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser());
 
-  localized_strings->SetBoolean("loggedInAsPublicAccount",
-      UserManager::Get()->IsLoggedInAsPublicAccount());
+  localized_strings->SetBoolean(
+      "loggedInAsPublicAccount",
+      user_manager::UserManager::Get()->IsLoggedInAsPublicAccount());
 }
 
 void AddAccountUITweaksLocalizedValues(
diff --git a/chrome/browser/ui/webui/extensions/chromeos/kiosk_apps_handler.cc b/chrome/browser/ui/webui/extensions/chromeos/kiosk_apps_handler.cc
index ceacefd..2a611c1 100644
--- a/chrome/browser/ui/webui/extensions/chromeos/kiosk_apps_handler.cc
+++ b/chrome/browser/ui/webui/extensions/chromeos/kiosk_apps_handler.cc
@@ -15,11 +15,11 @@
 #include "base/strings/string_util.h"
 #include "base/sys_info.h"
 #include "base/values.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/settings/cros_settings_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/web_ui.h"
 #include "content/public/browser/web_ui_data_source.h"
 #include "extensions/common/extension.h"
@@ -199,9 +199,8 @@ void KioskAppsHandler::OnKioskExtensionDownloadFailed(
 void KioskAppsHandler::OnGetConsumerKioskAutoLaunchStatus(
     chromeos::KioskAppManager::ConsumerKioskAutoLaunchStatus status) {
   initialized_ = true;
-  is_kiosk_enabled_ =
-      chromeos::UserManager::Get()->IsCurrentUserOwner() ||
-      !base::SysInfo::IsRunningOnChromeOS();
+  is_kiosk_enabled_ = user_manager::UserManager::Get()->IsCurrentUserOwner() ||
+                      !base::SysInfo::IsRunningOnChromeOS();
 
   is_auto_launch_enabled_ =
       status == KioskAppManager::CONSUMER_KIOSK_AUTO_LAUNCH_ENABLED ||
diff --git a/chrome/browser/ui/webui/flags_ui.cc b/chrome/browser/ui/webui/flags_ui.cc
index 64fe3d9..5301a5b 100644
--- a/chrome/browser/ui/webui/flags_ui.cc
+++ b/chrome/browser/ui/webui/flags_ui.cc
@@ -34,7 +34,6 @@
 
 #if defined(OS_CHROMEOS)
 #include "base/sys_info.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service_factory.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
@@ -42,6 +41,7 @@
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/session_manager_client.h"
 #include "components/pref_registry/pref_registry_syncable.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using content::WebContents;
@@ -75,7 +75,7 @@ content::WebUIDataSource* CreateFlagsUIHTMLSource() {
   source->AddLocalizedString("enable", IDS_FLAGS_ENABLE);
 
 #if defined(OS_CHROMEOS)
-  if (!chromeos::UserManager::Get()->IsCurrentUserOwner() &&
+  if (!user_manager::UserManager::Get()->IsCurrentUserOwner() &&
       base::SysInfo::IsRunningOnChromeOS()) {
     // Set the strings to show which user can actually change the flags.
     std::string owner;
@@ -231,9 +231,10 @@ void FlagsDOMHandler::HandleRestartBrowser(const base::ListValue* args) {
   // argv[0] is the program name |CommandLine::NO_PROGRAM|.
   flags.assign(user_flags.argv().begin() + 1, user_flags.argv().end());
   VLOG(1) << "Restarting to apply per-session flags...";
-  chromeos::DBusThreadManager::Get()->GetSessionManagerClient()->
-      SetFlagsForUser(chromeos::UserManager::Get()->GetActiveUser()->email(),
-                      flags);
+  chromeos::DBusThreadManager::Get()
+      ->GetSessionManagerClient()
+      ->SetFlagsForUser(
+          user_manager::UserManager::Get()->GetActiveUser()->email(), flags);
 #endif
   chrome::AttemptRestart();
 }
diff --git a/chrome/browser/ui/webui/help/help_handler.cc b/chrome/browser/ui/webui/help/help_handler.cc
index 9fca84e..5ec3aa5 100644
--- a/chrome/browser/ui/webui/help/help_handler.cc
+++ b/chrome/browser/ui/webui/help/help_handler.cc
@@ -44,7 +44,6 @@
 #include "base/i18n/time_formatting.h"
 #include "base/prefs/pref_service.h"
 #include "base/sys_info.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/profiles/profile.h"
@@ -52,6 +51,7 @@
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/power_manager_client.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using base::ListValue;
@@ -92,14 +92,15 @@ bool CanChangeChannel() {
       return false;
     // Get the currently logged in user and strip the domain part only.
     std::string domain = "";
-    std::string user = chromeos::UserManager::Get()->GetLoggedInUser()->email();
+    std::string user =
+        user_manager::UserManager::Get()->GetLoggedInUser()->email();
     size_t at_pos = user.find('@');
     if (at_pos != std::string::npos && at_pos + 1 < user.length())
       domain = user.substr(user.find('@') + 1);
     policy::BrowserPolicyConnectorChromeOS* connector =
         g_browser_process->platform_part()->browser_policy_connector_chromeos();
     return domain == connector->GetEnterpriseDomain();
-  } else if (chromeos::UserManager::Get()->IsCurrentUserOwner()) {
+  } else if (user_manager::UserManager::Get()->IsCurrentUserOwner()) {
     // On non managed machines we have local owner who is the only one to change
     // anything. Ensure that ReleaseChannelDelegated is false.
     return !value;
@@ -430,7 +431,7 @@ void HelpHandler::SetChannel(const base::ListValue* args) {
 
   version_updater_->SetChannel(base::UTF16ToUTF8(channel),
                                is_powerwash_allowed);
-  if (chromeos::UserManager::Get()->IsCurrentUserOwner()) {
+  if (user_manager::UserManager::Get()->IsCurrentUserOwner()) {
     // Check for update after switching release channel.
     version_updater_->CheckForUpdate(base::Bind(&HelpHandler::SetUpdateStatus,
                                                 base::Unretained(this)));
diff --git a/chrome/browser/ui/webui/help/version_updater_chromeos.cc b/chrome/browser/ui/webui/help/version_updater_chromeos.cc
index e6c2f2a..ac87357 100644
--- a/chrome/browser/ui/webui/help/version_updater_chromeos.cc
+++ b/chrome/browser/ui/webui/help/version_updater_chromeos.cc
@@ -10,7 +10,6 @@
 #include "base/bind_helpers.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/ui/webui/help/help_utils_chromeos.h"
@@ -20,6 +19,7 @@
 #include "chromeos/network/network_state.h"
 #include "chromeos/network/network_state_handler.h"
 #include "chromeos/settings/cros_settings_names.h"
+#include "components/user_manager/user_manager.h"
 #include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
@@ -28,7 +28,7 @@
 using chromeos::CrosSettings;
 using chromeos::DBusThreadManager;
 using chromeos::UpdateEngineClient;
-using chromeos::UserManager;
+using user_manager::UserManager;
 using chromeos::WizardController;
 
 namespace {
@@ -128,7 +128,7 @@ void VersionUpdaterCros::RelaunchBrowser() const {
 
 void VersionUpdaterCros::SetChannel(const std::string& channel,
                                     bool is_powerwash_allowed) {
-  if (UserManager::Get()->IsCurrentUserOwner()) {
+  if (user_manager::UserManager::Get()->IsCurrentUserOwner()) {
     // For local owner set the field in the policy blob.
     CrosSettings::Get()->SetString(chromeos::kReleaseChannel, channel);
   }
diff --git a/chrome/browser/ui/webui/options/browser_options_handler.cc b/chrome/browser/ui/webui/options/browser_options_handler.cc
index 84f0263..d33ad33 100644
--- a/chrome/browser/ui/webui/options/browser_options_handler.cc
+++ b/chrome/browser/ui/webui/options/browser_options_handler.cc
@@ -105,7 +105,6 @@
 #include "ash/shell.h"
 #include "chrome/browser/chromeos/accessibility/accessibility_util.h"
 #include "chrome/browser/chromeos/chromeos_utils.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
@@ -122,6 +121,7 @@
 #include "components/policy/core/common/policy_namespace.h"
 #include "components/policy/core/common/policy_service.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
 #include "policy/policy_constants.h"
 #include "policy/proto/device_management_backend.pb.h"
 #include "ui/gfx/image/image_skia.h"
@@ -942,8 +942,8 @@ void BrowserOptionsHandler::InitializePage() {
   policy::BrowserPolicyConnectorChromeOS* connector =
       g_browser_process->platform_part()->browser_policy_connector_chromeos();
   if (!connector->IsEnterpriseManaged() &&
-      !chromeos::UserManager::Get()->IsLoggedInAsGuest() &&
-      !chromeos::UserManager::Get()->IsLoggedInAsSupervisedUser()) {
+      !user_manager::UserManager::Get()->IsLoggedInAsGuest() &&
+      !user_manager::UserManager::Get()->IsLoggedInAsSupervisedUser()) {
     web_ui()->CallJavascriptFunction(
         "BrowserOptions.enableFactoryResetSection");
   }
@@ -958,7 +958,7 @@ void BrowserOptionsHandler::InitializePage() {
 
   OnWallpaperManagedChanged(
       chromeos::WallpaperManager::Get()->IsPolicyControlled(
-          chromeos::UserManager::Get()->GetActiveUser()->email()));
+          user_manager::UserManager::Get()->GetActiveUser()->email()));
 #endif
 }
 
@@ -1351,7 +1351,8 @@ void BrowserOptionsHandler::ThemesSetNative(const base::ListValue* args) {
 
 #if defined(OS_CHROMEOS)
 void BrowserOptionsHandler::UpdateAccountPicture() {
-  std::string email = chromeos::UserManager::Get()->GetLoggedInUser()->email();
+  std::string email =
+      user_manager::UserManager::Get()->GetLoggedInUser()->email();
   if (!email.empty()) {
     web_ui()->CallJavascriptFunction("BrowserOptions.updateAccountPicture");
     base::StringValue email_value(email);
diff --git a/chrome/browser/ui/webui/options/chromeos/accounts_options_browsertest.cc b/chrome/browser/ui/webui/options/chromeos/accounts_options_browsertest.cc
index f2b4880..db1d4fa 100644
--- a/chrome/browser/ui/webui/options/chromeos/accounts_options_browsertest.cc
+++ b/chrome/browser/ui/webui/options/chromeos/accounts_options_browsertest.cc
@@ -8,7 +8,6 @@
 #include "chrome/browser/chromeos/login/login_manager_test.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/stub_cros_settings_provider.h"
@@ -18,6 +17,7 @@
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "chromeos/settings/cros_settings_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/test/browser_test_utils.h"
 #include "content/public/test/test_utils.h"
@@ -136,7 +136,7 @@ IN_PROC_BROWSER_TEST_F(AccountsOptionsTest, MultiProfilesAccountsOptions) {
   content::RunAllPendingInMessageLoop();
   AddUser(kTestUsers[1]);
 
-  UserManager* manager = UserManager::Get();
+  user_manager::UserManager* manager = user_manager::UserManager::Get();
   ASSERT_EQ(2u, manager->GetLoggedInUsers().size());
 
   CheckAccountsUI(manager->FindUser(kTestUsers[0]), true /* is_owner */);
diff --git a/chrome/browser/ui/webui/options/chromeos/accounts_options_handler.cc b/chrome/browser/ui/webui/options/chromeos/accounts_options_handler.cc
index 856945f..f3c2ebb 100644
--- a/chrome/browser/ui/webui/options/chromeos/accounts_options_handler.cc
+++ b/chrome/browser/ui/webui/options/chromeos/accounts_options_handler.cc
@@ -14,11 +14,12 @@
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
+#include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/webui/chromeos/ui_account_tweaks.h"
 #include "chromeos/settings/cros_settings_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/web_ui.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 #include "grit/generated_resources.h"
@@ -115,7 +116,7 @@ void AccountsOptionsHandler::HandleUnwhitelistUser(
 
   base::StringValue canonical_email(gaia::CanonicalizeEmail(email));
   CrosSettings::Get()->RemoveFromList(kAccountsPrefUsers, &canonical_email);
-  UserManager::Get()->RemoveUser(email, NULL);
+  user_manager::UserManager::Get()->RemoveUser(email, NULL);
 }
 
 void AccountsOptionsHandler::HandleWhitelistExistingUsers(
@@ -134,7 +135,8 @@ void AccountsOptionsHandler::HandleWhitelistExistingUsers(
   else
     new_list.reset(new base::ListValue);
 
-  const user_manager::UserList& users = UserManager::Get()->GetUsers();
+  const user_manager::UserList& users =
+      user_manager::UserManager::Get()->GetUsers();
   for (user_manager::UserList::const_iterator it = users.begin();
        it < users.end();
        ++it)
diff --git a/chrome/browser/ui/webui/options/chromeos/change_picture_options_handler.cc b/chrome/browser/ui/webui/options/chromeos/change_picture_options_handler.cc
index bf64a89..4e95b8d 100644
--- a/chrome/browser/ui/webui/options/chromeos/change_picture_options_handler.cc
+++ b/chrome/browser/ui/webui/options/chromeos/change_picture_options_handler.cc
@@ -16,7 +16,7 @@
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/camera_presence_notifier.h"
 #include "chrome/browser/chromeos/login/users/avatar/user_image_manager.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/chrome_user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/ui/browser_finder.h"
 #include "chrome/browser/ui/browser_window.h"
@@ -28,6 +28,7 @@
 #include "components/user_manager/user.h"
 #include "components/user_manager/user_image/default_user_images.h"
 #include "components/user_manager/user_image/user_image.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/web_ui.h"
@@ -312,7 +313,7 @@ void ChangePictureOptionsHandler::SendProfileImage(const gfx::ImageSkia& image,
 
 void ChangePictureOptionsHandler::UpdateProfileImage() {
   UserImageManager* user_image_manager =
-      UserManager::Get()->GetUserImageManager(GetUser()->email());
+      ChromeUserManager::Get()->GetUserImageManager(GetUser()->email());
   // If we have a downloaded profile image and haven't sent it in
   // |SendSelectedImage|, send it now (without selecting).
   if (previous_image_index_ != user_manager::User::USER_IMAGE_PROFILE &&
@@ -343,7 +344,7 @@ void ChangePictureOptionsHandler::HandleSelectImage(
   DCHECK(!image_type.empty());
 
   UserImageManager* user_image_manager =
-      UserManager::Get()->GetUserImageManager(GetUser()->email());
+      ChromeUserManager::Get()->GetUserImageManager(GetUser()->email());
   int image_index = user_manager::User::USER_IMAGE_INVALID;
   bool waiting_for_camera_photo = false;
 
@@ -403,9 +404,9 @@ void ChangePictureOptionsHandler::HandleSelectImage(
 void ChangePictureOptionsHandler::FileSelected(const base::FilePath& path,
                                                int index,
                                                void* params) {
-  UserManager* user_manager = UserManager::Get();
-  user_manager->GetUserImageManager(GetUser()->email())->
-      SaveUserImageFromFile(path);
+  ChromeUserManager::Get()
+      ->GetUserImageManager(GetUser()->email())
+      ->SaveUserImageFromFile(path);
   UMA_HISTOGRAM_ENUMERATION("UserImage.ChangeChoice",
                             user_manager::kHistogramImageFromFile,
                             user_manager::kHistogramImagesCount);
@@ -414,8 +415,8 @@ void ChangePictureOptionsHandler::FileSelected(const base::FilePath& path,
 
 void ChangePictureOptionsHandler::SetImageFromCamera(
     const gfx::ImageSkia& photo) {
-  UserManager* user_manager = UserManager::Get();
-  user_manager->GetUserImageManager(GetUser()->email())
+  ChromeUserManager::Get()
+      ->GetUserImageManager(GetUser()->email())
       ->SaveUserImage(user_manager::UserImage::CreateAndEncode(photo));
   UMA_HISTOGRAM_ENUMERATION("UserImage.ChangeChoice",
                             user_manager::kHistogramImageFromCamera,
@@ -475,7 +476,7 @@ user_manager::User* ChangePictureOptionsHandler::GetUser() const {
   Profile* profile = Profile::FromWebUI(web_ui());
   user_manager::User* user = ProfileHelper::Get()->GetUserByProfile(profile);
   if (!user)
-    return UserManager::Get()->GetActiveUser();
+    return user_manager::UserManager::Get()->GetActiveUser();
   return user;
 }
 
diff --git a/chrome/browser/ui/webui/options/chromeos/consumer_management_handler.cc b/chrome/browser/ui/webui/options/chromeos/consumer_management_handler.cc
index 8acec3a..d1d9044 100644
--- a/chrome/browser/ui/webui/options/chromeos/consumer_management_handler.cc
+++ b/chrome/browser/ui/webui/options/chromeos/consumer_management_handler.cc
@@ -8,10 +8,10 @@
 #include "base/bind_helpers.h"
 #include "base/logging.h"
 #include "base/values.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/consumer_management_service.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/power_manager_client.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/web_ui.h"
 #include "grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util.h"
@@ -77,7 +77,7 @@ void ConsumerManagementHandler::RegisterMessages() {
 
 void ConsumerManagementHandler::HandleEnrollConsumerManagement(
     const base::ListValue* args) {
-  if (!chromeos::UserManager::Get()->IsCurrentUserOwner()) {
+  if (!user_manager::UserManager::Get()->IsCurrentUserOwner()) {
     LOG(ERROR) << "Received enrollConsumerManagement, but the current user is "
                << "not the owner.";
     return;
diff --git a/chrome/browser/ui/webui/options/chromeos/core_chromeos_options_handler.cc b/chrome/browser/ui/webui/options/chromeos/core_chromeos_options_handler.cc
index c6bbe70..9795f4b 100644
--- a/chrome/browser/ui/webui/options/chromeos/core_chromeos_options_handler.cc
+++ b/chrome/browser/ui/webui/options/chromeos/core_chromeos_options_handler.cc
@@ -16,7 +16,6 @@
 #include "base/sys_info.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/proxy_cros_settings_parser.h"
@@ -27,6 +26,7 @@
 #include "chrome/browser/ui/webui/options/chromeos/accounts_options_handler.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/user_metrics.h"
 #include "content/public/browser/web_ui.h"
@@ -59,7 +59,7 @@ base::DictionaryValue* CreateUserInfo(const std::string& username,
   user_dict->SetString("name", display_email);
   user_dict->SetString("email", display_name);
 
-  bool is_owner = UserManager::Get()->GetOwnerEmail() == username;
+  bool is_owner = user_manager::UserManager::Get()->GetOwnerEmail() == username;
   user_dict->SetBoolean("owner", is_owner);
   return user_dict;
 }
@@ -70,7 +70,7 @@ base::Value* CreateUsersWhitelist(const base::Value *pref_value) {
   const base::ListValue* list_value =
       static_cast<const base::ListValue*>(pref_value);
   base::ListValue* user_list = new base::ListValue();
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
   for (base::ListValue::const_iterator i = list_value->begin();
        i != list_value->end(); ++i) {
@@ -246,7 +246,7 @@ base::Value* CoreChromeOSOptionsHandler::CreateValueForPref(
   // The screen lock setting is shared if multiple users are logged in and at
   // least one has chosen to require passwords.
   if (pref_name == prefs::kEnableAutoScreenLock &&
-      UserManager::Get()->GetLoggedInUsers().size() > 1 &&
+      user_manager::UserManager::Get()->GetLoggedInUsers().size() > 1 &&
       controlling_pref_name.empty()) {
     PrefService* user_prefs = Profile::FromWebUI(web_ui())->GetPrefs();
     const PrefService::Preference* pref =
@@ -283,7 +283,7 @@ void CoreChromeOSOptionsHandler::GetLocalizedValues(
   Profile* profile = Profile::FromWebUI(web_ui());
   AddAccountUITweaksLocalizedValues(localized_strings, profile);
 
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
   // Check at load time whether this is a secondary user in a multi-profile
   // session.
diff --git a/chrome/browser/ui/webui/options/chromeos/cros_language_options_handler.cc b/chrome/browser/ui/webui/options/chromeos/cros_language_options_handler.cc
index e31aa31..c4f599f 100644
--- a/chrome/browser/ui/webui/options/chromeos/cros_language_options_handler.cc
+++ b/chrome/browser/ui/webui/options/chromeos/cros_language_options_handler.cc
@@ -11,7 +11,6 @@
 #include "base/values.h"
 #include "chrome/app/chrome_command_ids.h"
 #include "chrome/browser/chromeos/input_method/input_method_util.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/extensions/extension_tab_util.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
@@ -25,6 +24,7 @@
 #include "chromeos/ime/component_extension_ime_manager.h"
 #include "chromeos/ime/extension_ime_util.h"
 #include "chromeos/ime/input_method_manager.h"
+#include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_type.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/user_metrics.h"
@@ -184,7 +184,7 @@ base::string16 CrosLanguageOptionsHandler::GetProductName() {
 void CrosLanguageOptionsHandler::SetApplicationLocale(
     const std::string& language_code) {
   Profile* profile = Profile::FromWebUI(web_ui());
-  UserManager* user_manager = UserManager::Get();
+  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
   // Secondary users and public session users cannot change the locale.
   user_manager::User* user = ProfileHelper::Get()->GetUserByProfile(profile);
diff --git a/chrome/browser/ui/webui/options/chromeos/shared_options_browsertest.cc b/chrome/browser/ui/webui/options/chromeos/shared_options_browsertest.cc
index 88dd983..b7dc0ec 100644
--- a/chrome/browser/ui/webui/options/chromeos/shared_options_browsertest.cc
+++ b/chrome/browser/ui/webui/options/chromeos/shared_options_browsertest.cc
@@ -9,7 +9,6 @@
 #include "chrome/browser/chromeos/login/login_manager_test.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/ui/user_adding_screen.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/stub_cros_settings_provider.h"
@@ -19,6 +18,7 @@
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "chromeos/settings/cros_settings_names.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/test/browser_test_utils.h"
 #include "content/public/test/test_utils.h"
@@ -273,7 +273,7 @@ IN_PROC_BROWSER_TEST_F(SharedOptionsTest, SharedOptions) {
   content::RunAllPendingInMessageLoop();
   AddUser(kTestNonOwner);
 
-  UserManager* manager = UserManager::Get();
+  user_manager::UserManager* manager = user_manager::UserManager::Get();
   ASSERT_EQ(2u, manager->GetLoggedInUsers().size());
   {
     SCOPED_TRACE("Checking settings for owner, primary user.");
@@ -304,7 +304,7 @@ IN_PROC_BROWSER_TEST_F(SharedOptionsTest, ScreenLockPreferencePrimary) {
   content::RunAllPendingInMessageLoop();
   AddUser(kTestNonOwner);
 
-  UserManager* manager = UserManager::Get();
+  user_manager::UserManager* manager = user_manager::UserManager::Get();
   const user_manager::User* user1 = manager->FindUser(kTestOwner);
   const user_manager::User* user2 = manager->FindUser(kTestNonOwner);
 
@@ -375,7 +375,7 @@ IN_PROC_BROWSER_TEST_F(SharedOptionsTest, ScreenLockPreferenceSecondary) {
   content::RunAllPendingInMessageLoop();
   AddUser(kTestNonOwner);
 
-  UserManager* manager = UserManager::Get();
+  user_manager::UserManager* manager = user_manager::UserManager::Get();
   const user_manager::User* user1 = manager->FindUser(kTestOwner);
   const user_manager::User* user2 = manager->FindUser(kTestNonOwner);
 
diff --git a/chrome/browser/ui/webui/options/chromeos/user_image_source.cc b/chrome/browser/ui/webui/options/chromeos/user_image_source.cc
index 54b1b46c..4ace6c1 100644
--- a/chrome/browser/ui/webui/options/chromeos/user_image_source.cc
+++ b/chrome/browser/ui/webui/options/chromeos/user_image_source.cc
@@ -7,9 +7,9 @@
 #include "base/memory/ref_counted_memory.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_split.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/common/url_constants.h"
 #include "components/user_manager/user_image/default_user_images.h"
+#include "components/user_manager/user_manager.h"
 #include "grit/theme_resources.h"
 #include "grit/ui_chromeos_resources.h"
 #include "net/base/escape.h"
@@ -39,7 +39,7 @@ base::RefCountedMemory* UserImageSource::GetUserImage(
     const std::string& email,
     ui::ScaleFactor scale_factor) const {
   const user_manager::User* user =
-      chromeos::UserManager::Get()->FindUser(email);
+      user_manager::UserManager::Get()->FindUser(email);
   if (user) {
     if (user->has_raw_image()) {
       return new base::RefCountedBytes(user->raw_image());
diff --git a/chrome/browser/ui/webui/options/content_settings_handler.cc b/chrome/browser/ui/webui/options/content_settings_handler.cc
index 531952e..c3ad979 100644
--- a/chrome/browser/ui/webui/options/content_settings_handler.cc
+++ b/chrome/browser/ui/webui/options/content_settings_handler.cc
@@ -52,7 +52,7 @@
 #include "ui/base/l10n/l10n_util.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "components/user_manager/user_manager.h"
 #endif
 
 using base::UserMetricsAction;
@@ -1316,7 +1316,7 @@ void ContentSettingsHandler::SetContentFilter(const base::ListValue* args) {
 #if defined(OS_CHROMEOS)
   // ChromeOS special case : in Guest mode settings are opened in Incognito
   // mode, so we need original profile to actually modify settings.
-  if (chromeos::UserManager::Get()->IsLoggedInAsGuest())
+  if (user_manager::UserManager::Get()->IsLoggedInAsGuest())
     profile = profile->GetOriginalProfile();
 #endif
 
diff --git a/chrome/browser/ui/webui/policy_ui.cc b/chrome/browser/ui/webui/policy_ui.cc
index b70dfc7..49eecaa 100644
--- a/chrome/browser/ui/webui/policy_ui.cc
+++ b/chrome/browser/ui/webui/policy_ui.cc
@@ -55,12 +55,12 @@
 #include "ui/base/l10n/time_format.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_cloud_policy_manager_chromeos.h"
 #include "chrome/browser/chromeos/policy/device_local_account_policy_service.h"
 #include "chrome/browser/chromeos/policy/user_cloud_policy_manager_chromeos.h"
 #include "chrome/browser/chromeos/policy/user_cloud_policy_manager_factory_chromeos.h"
+#include "components/user_manager/user_manager.h"
 #else
 #include "chrome/browser/policy/cloud/user_cloud_policy_manager_factory.h"
 #include "components/policy/core/common/cloud/user_cloud_policy_manager.h"
@@ -536,7 +536,8 @@ void PolicyUIHandler::RegisterMessages() {
   if (connector->IsEnterpriseManaged())
     device_status_provider_.reset(new DevicePolicyStatusProvider(connector));
 
-  const chromeos::UserManager* user_manager = chromeos::UserManager::Get();
+  const user_manager::UserManager* user_manager =
+      user_manager::UserManager::Get();
   if (user_manager->IsLoggedInAsPublicAccount()) {
     policy::DeviceLocalAccountPolicyService* local_account_service =
         connector->GetDeviceLocalAccountPolicyService();
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index 07d3bbc..3c7ba76 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -3182,6 +3182,7 @@
           ],
           'dependencies': [
             'browser_chromeos',
+            '../components/components.gyp:user_manager',
             '../ui/chromeos/ui_chromeos.gyp:ui_chromeos_resources',
           ],
         }, {  # Non-ChromeOS.
diff --git a/chrome/chrome_browser_chromeos.gypi b/chrome/chrome_browser_chromeos.gypi
index 4381318..67ce748 100644
--- a/chrome/chrome_browser_chromeos.gypi
+++ b/chrome/chrome_browser_chromeos.gypi
@@ -726,17 +726,18 @@
         'browser/chromeos/login/users/avatar/user_image_sync_observer.h',
         'browser/chromeos/login/users/chrome_user_manager.cc',
         'browser/chromeos/login/users/chrome_user_manager.h',
+        'browser/chromeos/login/users/chrome_user_manager_impl.cc',
+        'browser/chromeos/login/users/chrome_user_manager_impl.h',
         'browser/chromeos/login/users/multi_profile_user_controller.cc',
         'browser/chromeos/login/users/multi_profile_user_controller.h',
         'browser/chromeos/login/users/multi_profile_user_controller_delegate.h',
-        'browser/chromeos/login/users/remove_user_delegate.h',
+        'browser/chromeos/login/users/scoped_test_user_manager.cc',
+        'browser/chromeos/login/users/scoped_test_user_manager.h',
+        'browser/chromeos/login/users/scoped_user_manager_enabler.cc',
+        'browser/chromeos/login/users/scoped_user_manager_enabler.h',
         'browser/chromeos/login/users/supervised_user_manager.h',
         'browser/chromeos/login/users/supervised_user_manager_impl.cc',
         'browser/chromeos/login/users/supervised_user_manager_impl.h',
-        'browser/chromeos/login/users/user_manager.cc',
-        'browser/chromeos/login/users/user_manager.h',
-        'browser/chromeos/login/users/user_manager_base.cc',
-        'browser/chromeos/login/users/user_manager_base.h',
         'browser/chromeos/login/users/wallpaper/wallpaper_manager.cc',
         'browser/chromeos/login/users/wallpaper/wallpaper_manager.h',
         'browser/chromeos/login/version_info_updater.cc',
diff --git a/chrome/test/base/browser_with_test_window_test.h b/chrome/test/base/browser_with_test_window_test.h
index cc5cde8..cb65ebc 100644
--- a/chrome/test/base/browser_with_test_window_test.h
+++ b/chrome/test/base/browser_with_test_window_test.h
@@ -16,7 +16,7 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_CHROMEOS)
-#include "chrome/browser/chromeos/login/users/user_manager.h"
+#include "chrome/browser/chromeos/login/users/scoped_test_user_manager.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/chromeos/settings/device_settings_service.h"
 #endif
diff --git a/components/user_manager.gypi b/components/user_manager.gypi
index f65fb3a..8aa5e8c 100644
--- a/components/user_manager.gypi
+++ b/components/user_manager.gypi
@@ -16,12 +16,17 @@
     ],
     # Chrome OS user_manager sources.
     'user_manager_chromeos_sources': [
+      'user_manager/remove_user_delegate.h',
       'user_manager/user_image/default_user_images.cc',
       'user_manager/user_image/default_user_images.h',
       'user_manager/user_image/user_image.cc',
       'user_manager/user_image/user_image.h',
       'user_manager/user.cc',
       'user_manager/user.h',
+      'user_manager/user_manager.cc',
+      'user_manager/user_manager.h',
+      'user_manager/user_manager_base.cc',
+      'user_manager/user_manager_base.h',
       'user_manager/user_type.h',
     ],
   },
@@ -45,6 +50,8 @@
     'conditions': [
       ['chromeos == 1', {
         'dependencies': [
+          '<(DEPTH)/base/base.gyp:base_prefs',
+          '<(DEPTH)/components/components.gyp:session_manager_component',
           '<(DEPTH)/google_apis/google_apis.gyp:google_apis',
           '<(DEPTH)/ui/chromeos/ui_chromeos.gyp:ui_chromeos_resources',
           '<(DEPTH)/ui/chromeos/ui_chromeos.gyp:ui_chromeos_strings',
diff --git a/components/user_manager/DEPS b/components/user_manager/DEPS
index 2cbd1db..f3fe77c 100644
--- a/components/user_manager/DEPS
+++ b/components/user_manager/DEPS
@@ -1,5 +1,9 @@
 include_rules = [
+"+chromeos/chromeos_switches.h",
+"+chromeos/cryptohome/async_method_caller.h",
+"+chromeos/login/login_state.h",
 "+chromeos/login/user_names.h",
+"+components/session_manager/core/session_manager.h",
 "+google_apis/gaia/gaia_auth_util.h",
 "+grit/ui_chromeos_resources.h",
 "+grit/ui_chromeos_strings.h",
diff --git a/chrome/browser/chromeos/login/users/remove_user_delegate.h b/components/user_manager/remove_user_delegate.h
index efdb7ee..1077bda 100644
--- a/chrome/browser/chromeos/login/users/remove_user_delegate.h
+++ b/components/user_manager/remove_user_delegate.h
@@ -2,13 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_BROWSER_CHROMEOS_LOGIN_USERS_REMOVE_USER_DELEGATE_H_
-#define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_REMOVE_USER_DELEGATE_H_
+#ifndef COMPONENTS_USER_MANAGER_REMOVE_USER_DELEGATE_H_
+#define COMPONENTS_USER_MANAGER_REMOVE_USER_DELEGATE_H_
 
-namespace chromeos {
+#include "components/user_manager/user_manager_export.h"
+
+namespace user_manager {
 
 // Delegate to be used with |UserManager::RemoveUser|.
-class RemoveUserDelegate {
+class USER_MANAGER_EXPORT RemoveUserDelegate {
  public:
   // Called right before actual user removal process is initiated.
   virtual void OnBeforeUserRemoved(const std::string& username) = 0;
@@ -17,6 +19,6 @@ class RemoveUserDelegate {
   virtual void OnUserRemoved(const std::string& username) = 0;
 };
 
-}  // namespace chromeos
+}  // namespace user_manager
 
-#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_REMOVE_USER_DELEGATE_H_
+#endif  // COMPONENTS_USER_MANAGER_REMOVE_USER_DELEGATE_H_
diff --git a/components/user_manager/user.h b/components/user_manager/user.h
index 23e8230..5ff8a10 100644
--- a/components/user_manager/user.h
+++ b/components/user_manager/user.h
@@ -18,19 +18,20 @@
 #include "ui/gfx/image/image_skia.h"
 
 namespace chromeos {
-class ChromeUserManager;
+class ChromeUserManagerImpl;
 class FakeLoginUtils;
 class FakeUserManager;
 class MockUserManager;
 class SupervisedUserManagerImpl;
 class UserAddingScreenTest;
 class UserImageManagerImpl;
-class UserManagerBase;
 class UserSessionManager;
 }
 
 namespace user_manager {
 
+class UserManagerBase;
+
 // A class representing information about a previously logged in user.
 // Each user has a canonical email (username), returned by |email()| and
 // may have a different displayed email (in the raw form as entered by user),
@@ -148,10 +149,10 @@ class USER_MANAGER_EXPORT User : public UserInfo {
   bool is_profile_created() const { return profile_is_created_; }
 
  protected:
-  friend class chromeos::ChromeUserManager;
+  friend class UserManagerBase;
+  friend class chromeos::ChromeUserManagerImpl;
   friend class chromeos::SupervisedUserManagerImpl;
   friend class chromeos::UserImageManagerImpl;
-  friend class chromeos::UserManagerBase;
   friend class chromeos::UserSessionManager;
 
   // For testing:
diff --git a/components/user_manager/user_manager.cc b/components/user_manager/user_manager.cc
new file mode 100644
index 0000000..597407f
--- /dev/null
+++ b/components/user_manager/user_manager.cc
@@ -0,0 +1,85 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/user_manager/user_manager.h"
+
+#include "base/logging.h"
+
+namespace user_manager {
+
+UserManager* UserManager::instance = NULL;
+
+UserManager::Observer::~Observer() {
+}
+
+void UserManager::Observer::LocalStateChanged(UserManager* user_manager) {
+}
+
+void UserManager::UserSessionStateObserver::ActiveUserChanged(
+    const User* active_user) {
+}
+
+void UserManager::UserSessionStateObserver::UserAddedToSession(
+    const User* active_user) {
+}
+
+void UserManager::UserSessionStateObserver::ActiveUserHashChanged(
+    const std::string& hash) {
+}
+
+UserManager::UserSessionStateObserver::~UserSessionStateObserver() {
+}
+
+UserManager::UserAccountData::UserAccountData(
+    const base::string16& display_name,
+    const base::string16& given_name,
+    const std::string& locale)
+    : display_name_(display_name), given_name_(given_name), locale_(locale) {
+}
+
+UserManager::UserAccountData::~UserAccountData() {
+}
+
+void UserManager::Initialize() {
+  DCHECK(!UserManager::instance);
+  UserManager::SetInstance(this);
+}
+
+// static
+bool UserManager::IsInitialized() {
+  return UserManager::instance;
+}
+
+void UserManager::Destroy() {
+  DCHECK(UserManager::instance == this);
+  UserManager::SetInstance(NULL);
+}
+
+// static
+UserManager* user_manager::UserManager::Get() {
+  CHECK(UserManager::instance);
+  return UserManager::instance;
+}
+
+UserManager::~UserManager() {
+}
+
+// static
+void UserManager::SetInstance(UserManager* user_manager) {
+  UserManager::instance = user_manager;
+}
+
+// static
+UserManager* user_manager::UserManager::GetForTesting() {
+  return UserManager::instance;
+}
+
+// static
+UserManager* UserManager::SetForTesting(UserManager* user_manager) {
+  UserManager* previous_instance = UserManager::instance;
+  UserManager::instance = user_manager;
+  return previous_instance;
+}
+
+}  // namespace user_manager
diff --git a/chrome/browser/chromeos/login/users/user_manager.h b/components/user_manager/user_manager.h
index 8b2d961..e775279 100644
--- a/chrome/browser/chromeos/login/users/user_manager.h
+++ b/components/user_manager/user_manager.h
@@ -2,26 +2,28 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_BROWSER_CHROMEOS_LOGIN_USERS_USER_MANAGER_H_
-#define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_USER_MANAGER_H_
+#ifndef COMPONENTS_USER_MANAGER_USER_MANAGER_H_
+#define COMPONENTS_USER_MANAGER_USER_MANAGER_H_
 
 #include <string>
 
-#include "chrome/browser/chromeos/login/user_flow.h"
 #include "components/user_manager/user.h"
-
-class PrefRegistrySimple;
+#include "components/user_manager/user_manager_export.h"
 
 namespace chromeos {
+class ScopedUserManagerEnabler;
+}
+
+namespace user_manager {
 
-class MultiProfileUserController;
 class RemoveUserDelegate;
-class UserImageManager;
-class SupervisedUserManager;
 
-// Interface for UserManagerBase - provides a mechanism for discovering users
-// who have logged into this Chrome OS device before and updating that list.
-class UserManager {
+// Interface for UserManagerBase - that provides base implementation for
+// Chrome OS user management. Typical features:
+// * Get list of all know users (who have logged into this Chrome OS device)
+// * Keep track for logged in/LRU users, active user in multi-user session.
+// * Find/modify users, store user meta-data such as display name/email.
+class USER_MANAGER_EXPORT UserManager {
  public:
   // Interface that observers of UserManager must implement in order
   // to receive notification when local state preferences is changed
@@ -40,10 +42,10 @@ class UserManager {
   class UserSessionStateObserver {
    public:
     // Called when active user has changed.
-    virtual void ActiveUserChanged(const user_manager::User* active_user);
+    virtual void ActiveUserChanged(const User* active_user);
 
     // Called when another user got added to the existing session.
-    virtual void UserAddedToSession(const user_manager::User* added_user);
+    virtual void UserAddedToSession(const User* added_user);
 
     // Called right before notifying on user change so that those who rely
     // on user_id hash would be accessing up-to-date value.
@@ -72,12 +74,14 @@ class UserManager {
     DISALLOW_COPY_AND_ASSIGN(UserAccountData);
   };
 
-  // Creates the singleton instance. This method is not thread-safe and must be
-  // called from the main UI thread.
-  static void Initialize();
+  // Initializes UserManager instance to this. Normally should be called right
+  // after creation so that user_manager::UserManager::Get() doesn't fail.
+  // Tests could call this method if they are replacing existing UserManager
+  // instance with their own test instance.
+  void Initialize();
 
-  // Checks whether the singleton instance has been created already. This method
-  // is not thread-safe and must be called from the main UI thread.
+  // Checks whether the UserManager instance has been created already.
+  // This method is not thread-safe and must be called from the main UI thread.
   static bool IsInitialized();
 
   // Shuts down the UserManager. After this method has been called, the
@@ -86,27 +90,20 @@ class UserManager {
   // thread-safe and must be called from the main UI thread.
   virtual void Shutdown() = 0;
 
-  // Destroys the singleton instance. Always call Shutdown() first. This method
-  // is not thread-safe and must be called from the main UI thread.
-  static void Destroy();
+  // Sets UserManager instance to NULL. Always call Shutdown() first.
+  // This method is not thread-safe and must be called from the main UI thread.
+  void Destroy();
 
-  // Returns the singleton instance or |NULL| if the singleton has either not
-  // been created yet or is already destroyed. This method is not thread-safe
+  // Returns UserManager instance or will crash if it is |NULL| (has either not
+  // been created yet or is already destroyed). This method is not thread-safe
   // and must be called from the main UI thread.
   static UserManager* Get();
 
-  // Registers user manager preferences.
-  static void RegisterPrefs(PrefRegistrySimple* registry);
-
   virtual ~UserManager();
 
-  virtual MultiProfileUserController* GetMultiProfileUserController() = 0;
-  virtual UserImageManager* GetUserImageManager(const std::string& user_id) = 0;
-  virtual SupervisedUserManager* GetSupervisedUserManager() = 0;
-
   // Returns a list of users who have logged into this device previously. This
   // is sorted by last login date with the most recent user at the beginning.
-  virtual const user_manager::UserList& GetUsers() const = 0;
+  virtual const UserList& GetUsers() const = 0;
 
   // Returns list of users admitted for logging in into multi-profile session.
   // Users that have a policy that prevents them from being added to the
@@ -114,15 +111,15 @@ class UserManager {
   // are regular users (i.e. not a public session/supervised etc.).
   // Returns an empty list in case when primary user is not a regular one or
   // has a policy that prohibids it to be part of multi-profile session.
-  virtual user_manager::UserList GetUsersAdmittedForMultiProfile() const = 0;
+  virtual UserList GetUsersAdmittedForMultiProfile() const = 0;
 
   // Returns a list of users who are currently logged in.
-  virtual const user_manager::UserList& GetLoggedInUsers() const = 0;
+  virtual const UserList& GetLoggedInUsers() const = 0;
 
   // Returns a list of users who are currently logged in in the LRU order -
   // so the active user is the first one in the list. If there is no user logged
   // in, the current user will be returned.
-  virtual const user_manager::UserList& GetLRULoggedInUsers() const = 0;
+  virtual const UserList& GetLRULoggedInUsers() const = 0;
 
   // Returns a list of users who can unlock the device.
   // This list is based on policy and whether user is able to do unlock.
@@ -130,7 +127,7 @@ class UserManager {
   // * If user has primary-only policy then it is the only user in unlock users.
   // * Otherwise all users with unrestricted policy are added to this list.
   // All users that are unable to perform unlock are excluded from this list.
-  virtual user_manager::UserList GetUnlockUsers() const = 0;
+  virtual UserList GetUnlockUsers() const = 0;
 
   // Returns the email of the owner user. Returns an empty string if there is
   // no owner for the device.
@@ -173,34 +170,33 @@ class UserManager {
 
   // Returns the user with the given user id if found in the persistent
   // list or currently logged in as ephemeral. Returns |NULL| otherwise.
-  virtual const user_manager::User* FindUser(
-      const std::string& user_id) const = 0;
+  virtual const User* FindUser(const std::string& user_id) const = 0;
 
   // Returns the user with the given user id if found in the persistent
   // list or currently logged in as ephemeral. Returns |NULL| otherwise.
   // Same as FindUser but returns non-const pointer to User object.
-  virtual user_manager::User* FindUserAndModify(const std::string& user_id) = 0;
+  virtual User* FindUserAndModify(const std::string& user_id) = 0;
 
   // Returns the logged-in user.
   // TODO(nkostylev): Deprecate this call, move clients to GetActiveUser().
   // http://crbug.com/230852
-  virtual const user_manager::User* GetLoggedInUser() const = 0;
-  virtual user_manager::User* GetLoggedInUser() = 0;
+  virtual const User* GetLoggedInUser() const = 0;
+  virtual User* GetLoggedInUser() = 0;
 
   // Returns the logged-in user that is currently active within this session.
   // There could be multiple users logged in at the the same but for now
   // we support only one of them being active.
-  virtual const user_manager::User* GetActiveUser() const = 0;
-  virtual user_manager::User* GetActiveUser() = 0;
+  virtual const User* GetActiveUser() const = 0;
+  virtual User* GetActiveUser() = 0;
 
   // Returns the primary user of the current session. It is recorded for the
   // first signed-in user and does not change thereafter.
-  virtual const user_manager::User* GetPrimaryUser() const = 0;
+  virtual const User* GetPrimaryUser() const = 0;
 
   // Saves user's oauth token status in local state preferences.
   virtual void SaveUserOAuthStatus(
       const std::string& user_id,
-      user_manager::User::OAuthTokenStatus oauth_token_status) = 0;
+      User::OAuthTokenStatus oauth_token_status) = 0;
 
   // Saves a flag indicating whether online authentication against GAIA should
   // be enforced during the user's next sign-in.
@@ -230,8 +226,7 @@ class UserManager {
   // Returns the display email for user |user_id| if it is known (was
   // previously set by a |SaveUserDisplayEmail| call).
   // Otherwise, returns |user_id| itself.
-  virtual std::string GetUserDisplayEmail(
-      const std::string& user_id) const = 0;
+  virtual std::string GetUserDisplayEmail(const std::string& user_id) const = 0;
 
   // Returns true if current user is an owner.
   virtual bool IsCurrentUserOwner() const = 0;
@@ -283,25 +278,6 @@ class UserManager {
   virtual bool IsUserNonCryptohomeDataEphemeral(
       const std::string& user_id) const = 0;
 
-  // Method that allows to set |flow| for user identified by |user_id|.
-  // Flow should be set before login attempt.
-  // Takes ownership of the |flow|, |flow| will be deleted in case of login
-  // failure.
-  virtual void SetUserFlow(const std::string& user_id, UserFlow* flow) = 0;
-
-  // Return user flow for current user. Returns instance of DefaultUserFlow if
-  // no flow was defined for current user, or user is not logged in.
-  // Returned value should not be cached.
-  virtual UserFlow* GetCurrentUserFlow() const = 0;
-
-  // Return user flow for user identified by |user_id|. Returns instance of
-  // DefaultUserFlow if no flow was defined for user.
-  // Returned value should not be cached.
-  virtual UserFlow* GetUserFlow(const std::string& user_id) const = 0;
-
-  // Resets user flow for user identified by |user_id|.
-  virtual void ResetUserFlow(const std::string& user_id) = 0;
-
   virtual void AddObserver(Observer* obs) = 0;
   virtual void RemoveObserver(Observer* obs) = 0;
 
@@ -313,41 +289,28 @@ class UserManager {
   // Returns true if supervised users allowed.
   virtual bool AreSupervisedUsersAllowed() const = 0;
 
- private:
-  friend class ScopedUserManagerEnabler;
+ protected:
+  // Sets UserManager instance.
+  static void SetInstance(UserManager* user_manager);
 
-  // Sets the singleton to the given |user_manager|, taking ownership. Returns
-  // the previous value of the singleton, passing ownership.
-  static UserManager* SetForTesting(UserManager* user_manager);
-};
-
-// Helper class for unit tests. Initializes the UserManager singleton to the
-// given |user_manager| and tears it down again on destruction. If the singleton
-// had already been initialized, its previous value is restored after tearing
-// down |user_manager|.
-class ScopedUserManagerEnabler {
- public:
-  // Takes ownership of |user_manager|.
-  explicit ScopedUserManagerEnabler(UserManager* user_manager);
-  ~ScopedUserManagerEnabler();
+  // Pointer to the existing UserManager instance (if any).
+  // Usually is set by calling Initialize(), reset by calling Destroy().
+  // Not owned since specific implementation of UserManager should decide on its
+  // own appropriate owner. For src/chrome implementation such place is
+  // g_browser_process->platform_part().
+  static UserManager* instance;
 
  private:
-  UserManager* previous_user_manager_;
+  friend class chromeos::ScopedUserManagerEnabler;
 
-  DISALLOW_COPY_AND_ASSIGN(ScopedUserManagerEnabler);
-};
-
-// Helper class for unit tests. Initializes the UserManager singleton on
-// construction and tears it down again on destruction.
-class ScopedTestUserManager {
- public:
-  ScopedTestUserManager();
-  ~ScopedTestUserManager();
+  // Same as Get() but doesn't won't crash is current instance is NULL.
+  static UserManager* GetForTesting();
 
- private:
-  DISALLOW_COPY_AND_ASSIGN(ScopedTestUserManager);
+  // Sets UserManager instance to the given |user_manager|.
+  // Returns the previous value of the instance.
+  static UserManager* SetForTesting(UserManager* user_manager);
 };
 
-}  // namespace chromeos
+}  // namespace user_manager
 
-#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_USER_MANAGER_H_
+#endif  // COMPONENTS_USER_MANAGER_USER_MANAGER_H_
diff --git a/chrome/browser/chromeos/login/users/user_manager_base.cc b/components/user_manager/user_manager_base.cc
index d2d42e4..3914819 100644
--- a/chrome/browser/chromeos/login/users/user_manager_base.cc
+++ b/components/user_manager/user_manager_base.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/browser/chromeos/login/users/user_manager_base.h"
+#include "components/user_manager/user_manager_base.h"
 
 #include <cstddef>
 #include <set>
@@ -12,7 +12,9 @@
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/format_macros.h"
+#include "base/location.h"
 #include "base/logging.h"
+#include "base/macros.h"
 #include "base/metrics/histogram.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service.h"
@@ -20,21 +22,19 @@
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/task_runner.h"
 #include "base/values.h"
-#include "chrome/browser/chromeos/login/users/remove_user_delegate.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/cryptohome/async_method_caller.h"
 #include "chromeos/login/login_state.h"
 #include "chromeos/login/user_names.h"
 #include "components/session_manager/core/session_manager.h"
+#include "components/user_manager/remove_user_delegate.h"
 #include "components/user_manager/user_type.h"
-#include "content/public/browser/browser_thread.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 #include "ui/base/l10n/l10n_util.h"
 
-using content::BrowserThread;
-
-namespace chromeos {
+namespace user_manager {
 namespace {
 
 // A vector pref of the the regular users known on this device, arranged in LRU
@@ -77,20 +77,6 @@ void OnRemoveUserComplete(const std::string& user_email,
   }
 }
 
-// Runs on SequencedWorkerPool thread. Passes resolved locale to
-// |on_resolve_callback| on UI thread.
-void ResolveLocale(
-    const std::string& raw_locale,
-    base::Callback<void(const std::string&)> on_resolve_callback) {
-  DCHECK(!BrowserThread::CurrentlyOn(BrowserThread::UI));
-  std::string resolved_locale;
-  // Ignore result
-  l10n_util::CheckAndResolveLocale(raw_locale, &resolved_locale);
-  BrowserThread::PostTask(BrowserThread::UI,
-                          FROM_HERE,
-                          base::Bind(on_resolve_callback, resolved_locale));
-}
-
 }  // namespace
 
 // static
@@ -104,7 +90,9 @@ void UserManagerBase::RegisterPrefs(PrefRegistrySimple* registry) {
   registry->RegisterDictionaryPref(kUserForceOnlineSignin);
 }
 
-UserManagerBase::UserManagerBase()
+UserManagerBase::UserManagerBase(
+    scoped_refptr<base::TaskRunner> task_runner,
+    scoped_refptr<base::TaskRunner> blocking_task_runner)
     : active_user_(NULL),
       primary_user_(NULL),
       user_loading_stage_(STAGE_NOT_LOADED),
@@ -114,15 +102,15 @@ UserManagerBase::UserManagerBase()
       is_current_user_ephemeral_regular_user_(false),
       ephemeral_users_enabled_(false),
       manager_creation_time_(base::TimeTicks::Now()),
+      task_runner_(task_runner),
+      blocking_task_runner_(blocking_task_runner),
       weak_factory_(this) {
-  // UserManager instance should be used only on UI thread.
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   UpdateLoginState();
 }
 
 UserManagerBase::~UserManagerBase() {
   // Can't use STLDeleteElements because of the private destructor of User.
-  for (user_manager::UserList::iterator it = users_.begin(); it != users_.end();
+  for (UserList::iterator it = users_.begin(); it != users_.end();
        it = users_.erase(it)) {
     DeleteUser(*it);
   }
@@ -134,19 +122,19 @@ UserManagerBase::~UserManagerBase() {
 }
 
 void UserManagerBase::Shutdown() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 }
 
-const user_manager::UserList& UserManagerBase::GetUsers() const {
+const UserList& UserManagerBase::GetUsers() const {
   const_cast<UserManagerBase*>(this)->EnsureUsersLoaded();
   return users_;
 }
 
-const user_manager::UserList& UserManagerBase::GetLoggedInUsers() const {
+const UserList& UserManagerBase::GetLoggedInUsers() const {
   return logged_in_users_;
 }
 
-const user_manager::UserList& UserManagerBase::GetLRULoggedInUsers() const {
+const UserList& UserManagerBase::GetLRULoggedInUsers() const {
   return lru_logged_in_users_;
 }
 
@@ -157,9 +145,9 @@ const std::string& UserManagerBase::GetOwnerEmail() const {
 void UserManagerBase::UserLoggedIn(const std::string& user_id,
                                    const std::string& username_hash,
                                    bool browser_restart) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 
-  user_manager::User* user = FindUserInListAndModify(user_id);
+  User* user = FindUserInListAndModify(user_id);
   if (active_user_ && user) {
     user->set_is_logged_in(true);
     user->set_username_hash(username_hash);
@@ -184,17 +172,15 @@ void UserManagerBase::UserLoggedIn(const std::string& user_id,
   } else {
     EnsureUsersLoaded();
 
-    if (user && user->GetType() == user_manager::USER_TYPE_PUBLIC_ACCOUNT) {
+    if (user && user->GetType() == USER_TYPE_PUBLIC_ACCOUNT) {
       PublicAccountUserLoggedIn(user);
-    } else if ((user &&
-                user->GetType() == user_manager::USER_TYPE_SUPERVISED) ||
+    } else if ((user && user->GetType() == USER_TYPE_SUPERVISED) ||
                (!user &&
                 gaia::ExtractDomainName(user_id) ==
                     chromeos::login::kSupervisedUserDomain)) {
       SupervisedUserLoggedIn(user_id);
     } else if (browser_restart && IsPublicAccountMarkedForRemoval(user_id)) {
-      PublicAccountUserLoggedIn(
-          user_manager::User::CreatePublicAccountUser(user_id));
+      PublicAccountUserLoggedIn(User::CreatePublicAccountUser(user_id));
     } else if (user_id != GetOwnerEmail() && !user &&
                (AreEphemeralUsersEnabled() || browser_restart)) {
       RegularUserLoggedInAsEphemeral(user_id);
@@ -214,25 +200,23 @@ void UserManagerBase::UserLoggedIn(const std::string& user_id,
 
   if (!primary_user_) {
     primary_user_ = active_user_;
-    if (primary_user_->GetType() == user_manager::USER_TYPE_REGULAR)
+    if (primary_user_->GetType() == USER_TYPE_REGULAR)
       SendRegularUserLoginMetrics(user_id);
   }
 
-  UMA_HISTOGRAM_ENUMERATION("UserManager.LoginUserType",
-                            active_user_->GetType(),
-                            user_manager::NUM_USER_TYPES);
+  UMA_HISTOGRAM_ENUMERATION(
+      "UserManager.LoginUserType", active_user_->GetType(), NUM_USER_TYPES);
 
   GetLocalState()->SetString(
       kLastLoggedInRegularUser,
-      (active_user_->GetType() == user_manager::USER_TYPE_REGULAR) ? user_id
-                                                                   : "");
+      (active_user_->GetType() == USER_TYPE_REGULAR) ? user_id : "");
 
   NotifyOnLogin();
   PerformPostUserLoggedInActions(browser_restart);
 }
 
 void UserManagerBase::SwitchActiveUser(const std::string& user_id) {
-  user_manager::User* user = FindUserAndModify(user_id);
+  User* user = FindUserAndModify(user_id);
   if (!user) {
     NOTREACHED() << "Switching to a non-existing user";
     return;
@@ -245,7 +229,7 @@ void UserManagerBase::SwitchActiveUser(const std::string& user_id) {
     NOTREACHED() << "Switching to a user that is not logged in";
     return;
   }
-  if (user->GetType() != user_manager::USER_TYPE_REGULAR) {
+  if (user->GetType() != USER_TYPE_REGULAR) {
     NOTREACHED() << "Switching to a non-regular user";
     return;
   }
@@ -267,7 +251,7 @@ void UserManagerBase::SwitchActiveUser(const std::string& user_id) {
 }
 
 void UserManagerBase::SessionStarted() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   session_started_ = true;
 
   UpdateLoginState();
@@ -282,7 +266,7 @@ void UserManagerBase::SessionStarted() {
 
 void UserManagerBase::RemoveUser(const std::string& user_id,
                                  RemoveUserDelegate* delegate) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 
   if (!CanUserBeRemoved(FindUser(user_id)))
     return;
@@ -308,7 +292,7 @@ void UserManagerBase::RemoveNonOwnerUserInternal(const std::string& user_email,
 }
 
 void UserManagerBase::RemoveUserFromList(const std::string& user_id) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   RemoveNonCryptohomeData(user_id);
   if (user_loading_stage_ == STAGE_LOADED) {
     DeleteUser(RemoveRegularOrSupervisedUserFromList(user_id));
@@ -332,54 +316,52 @@ bool UserManagerBase::IsKnownUser(const std::string& user_id) const {
   return FindUser(user_id) != NULL;
 }
 
-const user_manager::User* UserManagerBase::FindUser(
-    const std::string& user_id) const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+const User* UserManagerBase::FindUser(const std::string& user_id) const {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   if (active_user_ && active_user_->email() == user_id)
     return active_user_;
   return FindUserInList(user_id);
 }
 
-user_manager::User* UserManagerBase::FindUserAndModify(
-    const std::string& user_id) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+User* UserManagerBase::FindUserAndModify(const std::string& user_id) {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   if (active_user_ && active_user_->email() == user_id)
     return active_user_;
   return FindUserInListAndModify(user_id);
 }
 
-const user_manager::User* UserManagerBase::GetLoggedInUser() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+const User* UserManagerBase::GetLoggedInUser() const {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return active_user_;
 }
 
-user_manager::User* UserManagerBase::GetLoggedInUser() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+User* UserManagerBase::GetLoggedInUser() {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return active_user_;
 }
 
-const user_manager::User* UserManagerBase::GetActiveUser() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+const User* UserManagerBase::GetActiveUser() const {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return active_user_;
 }
 
-user_manager::User* UserManagerBase::GetActiveUser() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+User* UserManagerBase::GetActiveUser() {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return active_user_;
 }
 
-const user_manager::User* UserManagerBase::GetPrimaryUser() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+const User* UserManagerBase::GetPrimaryUser() const {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return primary_user_;
 }
 
 void UserManagerBase::SaveUserOAuthStatus(
     const std::string& user_id,
-    user_manager::User::OAuthTokenStatus oauth_token_status) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    User::OAuthTokenStatus oauth_token_status) {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 
   DVLOG(1) << "Saving user OAuth token status in Local State";
-  user_manager::User* user = FindUserAndModify(user_id);
+  User* user = FindUserAndModify(user_id);
   if (user)
     user->set_oauth_token_status(oauth_token_status);
 
@@ -397,7 +379,7 @@ void UserManagerBase::SaveUserOAuthStatus(
 
 void UserManagerBase::SaveForceOnlineSignin(const std::string& user_id,
                                             bool force_online_signin) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 
   // Do not update local state if data stored or cached outside the user's
   // cryptohome is to be treated as ephemeral.
@@ -412,9 +394,9 @@ void UserManagerBase::SaveForceOnlineSignin(const std::string& user_id,
 
 void UserManagerBase::SaveUserDisplayName(const std::string& user_id,
                                           const base::string16& display_name) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 
-  if (user_manager::User* user = FindUserAndModify(user_id)) {
+  if (User* user = FindUserAndModify(user_id)) {
     user->set_display_name(display_name);
 
     // Do not update local state if data stored or cached outside the user's
@@ -430,15 +412,15 @@ void UserManagerBase::SaveUserDisplayName(const std::string& user_id,
 
 base::string16 UserManagerBase::GetUserDisplayName(
     const std::string& user_id) const {
-  const user_manager::User* user = FindUser(user_id);
+  const User* user = FindUser(user_id);
   return user ? user->display_name() : base::string16();
 }
 
 void UserManagerBase::SaveUserDisplayEmail(const std::string& user_id,
                                            const std::string& display_email) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 
-  user_manager::User* user = FindUserAndModify(user_id);
+  User* user = FindUserAndModify(user_id);
   if (!user)
     return;  // Ignore if there is no such user.
 
@@ -456,18 +438,18 @@ void UserManagerBase::SaveUserDisplayEmail(const std::string& user_id,
 
 std::string UserManagerBase::GetUserDisplayEmail(
     const std::string& user_id) const {
-  const user_manager::User* user = FindUser(user_id);
+  const User* user = FindUser(user_id);
   return user ? user->display_email() : user_id;
 }
 
 void UserManagerBase::UpdateUserAccountData(
     const std::string& user_id,
     const UserAccountData& account_data) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 
   SaveUserDisplayName(user_id, account_data.display_name());
 
-  if (user_manager::User* user = FindUserAndModify(user_id)) {
+  if (User* user = FindUserAndModify(user_id)) {
     base::string16 given_name = account_data.given_name();
     user->set_given_name(given_name);
     if (!IsUserNonCryptohomeDataEphemeral(user_id)) {
@@ -503,13 +485,13 @@ void UserManagerBase::ParseUserList(const base::ListValue& users_list,
 }
 
 bool UserManagerBase::IsCurrentUserOwner() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   base::AutoLock lk(is_current_user_owner_lock_);
   return is_current_user_owner_;
 }
 
 void UserManagerBase::SetCurrentUserIsOwner(bool is_current_user_owner) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   {
     base::AutoLock lk(is_current_user_owner_lock_);
     is_current_user_owner_ = is_current_user_owner;
@@ -518,69 +500,65 @@ void UserManagerBase::SetCurrentUserIsOwner(bool is_current_user_owner) {
 }
 
 bool UserManagerBase::IsCurrentUserNew() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return is_current_user_new_;
 }
 
 bool UserManagerBase::IsCurrentUserNonCryptohomeDataEphemeral() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return IsUserLoggedIn() &&
          IsUserNonCryptohomeDataEphemeral(GetLoggedInUser()->email());
 }
 
 bool UserManagerBase::CanCurrentUserLock() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return IsUserLoggedIn() && active_user_->can_lock();
 }
 
 bool UserManagerBase::IsUserLoggedIn() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return active_user_;
 }
 
 bool UserManagerBase::IsLoggedInAsRegularUser() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  return IsUserLoggedIn() &&
-         active_user_->GetType() == user_manager::USER_TYPE_REGULAR;
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
+  return IsUserLoggedIn() && active_user_->GetType() == USER_TYPE_REGULAR;
 }
 
 bool UserManagerBase::IsLoggedInAsDemoUser() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  return IsUserLoggedIn() &&
-         active_user_->GetType() == user_manager::USER_TYPE_RETAIL_MODE;
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
+  return IsUserLoggedIn() && active_user_->GetType() == USER_TYPE_RETAIL_MODE;
 }
 
 bool UserManagerBase::IsLoggedInAsPublicAccount() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return IsUserLoggedIn() &&
-         active_user_->GetType() == user_manager::USER_TYPE_PUBLIC_ACCOUNT;
+         active_user_->GetType() == USER_TYPE_PUBLIC_ACCOUNT;
 }
 
 bool UserManagerBase::IsLoggedInAsGuest() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  return IsUserLoggedIn() &&
-         active_user_->GetType() == user_manager::USER_TYPE_GUEST;
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
+  return IsUserLoggedIn() && active_user_->GetType() == USER_TYPE_GUEST;
 }
 
 bool UserManagerBase::IsLoggedInAsSupervisedUser() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  return IsUserLoggedIn() &&
-         active_user_->GetType() == user_manager::USER_TYPE_SUPERVISED;
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
+  return IsUserLoggedIn() && active_user_->GetType() == USER_TYPE_SUPERVISED;
 }
 
 bool UserManagerBase::IsLoggedInAsKioskApp() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  return IsUserLoggedIn() &&
-         active_user_->GetType() == user_manager::USER_TYPE_KIOSK_APP;
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
+  return IsUserLoggedIn() && active_user_->GetType() == USER_TYPE_KIOSK_APP;
 }
 
 bool UserManagerBase::IsLoggedInAsStub() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  return IsUserLoggedIn() && active_user_->email() == login::kStubUser;
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
+  return IsUserLoggedIn() &&
+         active_user_->email() == chromeos::login::kStubUser;
 }
 
 bool UserManagerBase::IsSessionStarted() const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   return session_started_;
 }
 
@@ -588,8 +566,9 @@ bool UserManagerBase::IsUserNonCryptohomeDataEphemeral(
     const std::string& user_id) const {
   // Data belonging to the guest, retail mode and stub users is always
   // ephemeral.
-  if (user_id == login::kGuestUserName ||
-      user_id == login::kRetailModeUserName || user_id == login::kStubUser) {
+  if (user_id == chromeos::login::kGuestUserName ||
+      user_id == chromeos::login::kRetailModeUserName ||
+      user_id == chromeos::login::kStubUser) {
     return true;
   }
 
@@ -620,37 +599,37 @@ bool UserManagerBase::IsUserNonCryptohomeDataEphemeral(
 }
 
 void UserManagerBase::AddObserver(UserManager::Observer* obs) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   observer_list_.AddObserver(obs);
 }
 
 void UserManagerBase::RemoveObserver(UserManager::Observer* obs) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   observer_list_.RemoveObserver(obs);
 }
 
 void UserManagerBase::AddSessionStateObserver(
     UserManager::UserSessionStateObserver* obs) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   session_state_observer_list_.AddObserver(obs);
 }
 
 void UserManagerBase::RemoveSessionStateObserver(
     UserManager::UserSessionStateObserver* obs) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   session_state_observer_list_.RemoveObserver(obs);
 }
 
 void UserManagerBase::NotifyLocalStateChanged() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   FOR_EACH_OBSERVER(
       UserManager::Observer, observer_list_, LocalStateChanged(this));
 }
 
-bool UserManagerBase::CanUserBeRemoved(const user_manager::User* user) const {
+bool UserManagerBase::CanUserBeRemoved(const User* user) const {
   // Only regular and supervised users are allowed to be manually removed.
-  if (!user || (user->GetType() != user_manager::USER_TYPE_REGULAR &&
-                user->GetType() != user_manager::USER_TYPE_SUPERVISED)) {
+  if (!user || (user->GetType() != USER_TYPE_REGULAR &&
+                user->GetType() != USER_TYPE_SUPERVISED)) {
     return false;
   }
 
@@ -664,7 +643,7 @@ bool UserManagerBase::CanUserBeRemoved(const user_manager::User* user) const {
     return false;
 
   // Sanity check: do not allow any of the the logged in users to be removed.
-  for (user_manager::UserList::const_iterator it = logged_in_users_.begin();
+  for (UserList::const_iterator it = logged_in_users_.begin();
        it != logged_in_users_.end();
        ++it) {
     if ((*it)->email() == user->email())
@@ -699,7 +678,7 @@ void UserManagerBase::SetPendingUserSwitchID(std::string user_id) {
 }
 
 void UserManagerBase::EnsureUsersLoaded() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   if (!GetLocalState())
     return;
 
@@ -734,12 +713,12 @@ void UserManagerBase::EnsureUsersLoaded() {
   for (std::vector<std::string>::const_iterator it = regular_users.begin();
        it != regular_users.end();
        ++it) {
-    user_manager::User* user = NULL;
+    User* user = NULL;
     const std::string domain = gaia::ExtractDomainName(*it);
     if (domain == chromeos::login::kSupervisedUserDomain)
-      user = user_manager::User::CreateSupervisedUser(*it);
+      user = User::CreateSupervisedUser(*it);
     else
-      user = user_manager::User::CreateRegularUser(*it);
+      user = User::CreateRegularUser(*it);
     user->set_oauth_token_status(LoadUserOAuthStatus(*it));
     user->set_force_online_signin(LoadForceOnlineSignin(*it));
     users_.push_back(user);
@@ -767,17 +746,14 @@ void UserManagerBase::EnsureUsersLoaded() {
   PerformPostUserListLoadingActions();
 }
 
-user_manager::UserList& UserManagerBase::GetUsersAndModify() {
+UserList& UserManagerBase::GetUsersAndModify() {
   EnsureUsersLoaded();
   return users_;
 }
 
-const user_manager::User* UserManagerBase::FindUserInList(
-    const std::string& user_id) const {
-  const user_manager::UserList& users = GetUsers();
-  for (user_manager::UserList::const_iterator it = users.begin();
-       it != users.end();
-       ++it) {
+const User* UserManagerBase::FindUserInList(const std::string& user_id) const {
+  const UserList& users = GetUsers();
+  for (UserList::const_iterator it = users.begin(); it != users.end(); ++it) {
     if ((*it)->email() == user_id)
       return *it;
   }
@@ -794,11 +770,9 @@ const bool UserManagerBase::UserExistsInList(const std::string& user_id) const {
   return false;
 }
 
-user_manager::User* UserManagerBase::FindUserInListAndModify(
-    const std::string& user_id) {
-  user_manager::UserList& users = GetUsersAndModify();
-  for (user_manager::UserList::iterator it = users.begin(); it != users.end();
-       ++it) {
+User* UserManagerBase::FindUserInListAndModify(const std::string& user_id) {
+  UserList& users = GetUsersAndModify();
+  for (UserList::iterator it = users.begin(); it != users.end(); ++it) {
     if ((*it)->email() == user_id)
       return *it;
   }
@@ -806,11 +780,11 @@ user_manager::User* UserManagerBase::FindUserInListAndModify(
 }
 
 void UserManagerBase::GuestUserLoggedIn() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  active_user_ = user_manager::User::CreateGuestUser();
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
+  active_user_ = User::CreateGuestUser();
 }
 
-void UserManagerBase::AddUserRecord(user_manager::User* user) {
+void UserManagerBase::AddUserRecord(User* user) {
   // Add the user to the front of the user list.
   ListPrefUpdate prefs_users_update(GetLocalState(), kRegularUsers);
   prefs_users_update->Insert(0, new base::StringValue(user->email()));
@@ -824,7 +798,7 @@ void UserManagerBase::RegularUserLoggedIn(const std::string& user_id) {
   // If the user was not found on the user list, create a new user.
   SetIsCurrentUserNew(!active_user_);
   if (IsCurrentUserNew()) {
-    active_user_ = user_manager::User::CreateRegularUser(user_id);
+    active_user_ = User::CreateRegularUser(user_id);
     active_user_->set_oauth_token_status(LoadUserOAuthStatus(user_id));
     SaveUserDisplayName(active_user_->email(),
                         base::UTF8ToUTF16(active_user_->GetAccountName(true)));
@@ -838,41 +812,41 @@ void UserManagerBase::RegularUserLoggedIn(const std::string& user_id) {
 
 void UserManagerBase::RegularUserLoggedInAsEphemeral(
     const std::string& user_id) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   SetIsCurrentUserNew(true);
   is_current_user_ephemeral_regular_user_ = true;
-  active_user_ = user_manager::User::CreateRegularUser(user_id);
+  active_user_ = User::CreateRegularUser(user_id);
 }
 
 void UserManagerBase::NotifyOnLogin() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 
   NotifyActiveUserHashChanged(active_user_->username_hash());
   NotifyActiveUserChanged(active_user_);
   UpdateLoginState();
 }
 
-user_manager::User::OAuthTokenStatus UserManagerBase::LoadUserOAuthStatus(
+User::OAuthTokenStatus UserManagerBase::LoadUserOAuthStatus(
     const std::string& user_id) const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 
   const base::DictionaryValue* prefs_oauth_status =
       GetLocalState()->GetDictionary(kUserOAuthTokenStatus);
-  int oauth_token_status = user_manager::User::OAUTH_TOKEN_STATUS_UNKNOWN;
+  int oauth_token_status = User::OAUTH_TOKEN_STATUS_UNKNOWN;
   if (prefs_oauth_status &&
       prefs_oauth_status->GetIntegerWithoutPathExpansion(user_id,
                                                          &oauth_token_status)) {
-    user_manager::User::OAuthTokenStatus result =
-        static_cast<user_manager::User::OAuthTokenStatus>(oauth_token_status);
-    if (result == user_manager::User::OAUTH2_TOKEN_STATUS_INVALID)
-      GetUserFlow(user_id)->HandleOAuthTokenStatusChange(result);
-    return result;
+    User::OAuthTokenStatus status =
+        static_cast<User::OAuthTokenStatus>(oauth_token_status);
+    HandleUserOAuthTokenStatusChange(user_id, status);
+
+    return status;
   }
-  return user_manager::User::OAUTH_TOKEN_STATUS_UNKNOWN;
+  return User::OAUTH_TOKEN_STATUS_UNKNOWN;
 }
 
 bool UserManagerBase::LoadForceOnlineSignin(const std::string& user_id) const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
 
   const base::DictionaryValue* prefs_force_online =
       GetLocalState()->GetDictionary(kUserForceOnlineSignin);
@@ -902,20 +876,19 @@ void UserManagerBase::RemoveNonCryptohomeData(const std::string& user_id) {
   prefs_force_online_update->RemoveWithoutPathExpansion(user_id, NULL);
 }
 
-user_manager::User* UserManagerBase::RemoveRegularOrSupervisedUserFromList(
+User* UserManagerBase::RemoveRegularOrSupervisedUserFromList(
     const std::string& user_id) {
   ListPrefUpdate prefs_users_update(GetLocalState(), kRegularUsers);
   prefs_users_update->Clear();
-  user_manager::User* user = NULL;
-  for (user_manager::UserList::iterator it = users_.begin();
-       it != users_.end();) {
+  User* user = NULL;
+  for (UserList::iterator it = users_.begin(); it != users_.end();) {
     const std::string user_email = (*it)->email();
     if (user_email == user_id) {
       user = *it;
       it = users_.erase(it);
     } else {
-      if ((*it)->GetType() == user_manager::USER_TYPE_REGULAR ||
-          (*it)->GetType() == user_manager::USER_TYPE_SUPERVISED) {
+      if ((*it)->GetType() == USER_TYPE_REGULAR ||
+          (*it)->GetType() == USER_TYPE_SUPERVISED) {
         prefs_users_update->Append(new base::StringValue(user_email));
       }
       ++it;
@@ -924,66 +897,65 @@ user_manager::User* UserManagerBase::RemoveRegularOrSupervisedUserFromList(
   return user;
 }
 
-void UserManagerBase::NotifyActiveUserChanged(
-    const user_manager::User* active_user) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+void UserManagerBase::NotifyActiveUserChanged(const User* active_user) {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   FOR_EACH_OBSERVER(UserManager::UserSessionStateObserver,
                     session_state_observer_list_,
                     ActiveUserChanged(active_user));
 }
 
-void UserManagerBase::NotifyUserAddedToSession(
-    const user_manager::User* added_user,
-    bool user_switch_pending) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+void UserManagerBase::NotifyUserAddedToSession(const User* added_user,
+                                               bool user_switch_pending) {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   FOR_EACH_OBSERVER(UserManager::UserSessionStateObserver,
                     session_state_observer_list_,
                     UserAddedToSession(added_user));
 }
 
 void UserManagerBase::NotifyActiveUserHashChanged(const std::string& hash) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
   FOR_EACH_OBSERVER(UserManager::UserSessionStateObserver,
                     session_state_observer_list_,
                     ActiveUserHashChanged(hash));
 }
 
 void UserManagerBase::UpdateLoginState() {
-  if (!LoginState::IsInitialized())
+  if (!chromeos::LoginState::IsInitialized())
     return;  // LoginState may not be intialized in tests.
 
-  LoginState::LoggedInState logged_in_state;
-  logged_in_state =
-      active_user_ ? LoginState::LOGGED_IN_ACTIVE : LoginState::LOGGED_IN_NONE;
+  chromeos::LoginState::LoggedInState logged_in_state;
+  logged_in_state = active_user_ ? chromeos::LoginState::LOGGED_IN_ACTIVE
+                                 : chromeos::LoginState::LOGGED_IN_NONE;
 
-  LoginState::LoggedInUserType login_user_type;
-  if (logged_in_state == LoginState::LOGGED_IN_NONE)
-    login_user_type = LoginState::LOGGED_IN_USER_NONE;
+  chromeos::LoginState::LoggedInUserType login_user_type;
+  if (logged_in_state == chromeos::LoginState::LOGGED_IN_NONE)
+    login_user_type = chromeos::LoginState::LOGGED_IN_USER_NONE;
   else if (is_current_user_owner_)
-    login_user_type = LoginState::LOGGED_IN_USER_OWNER;
-  else if (active_user_->GetType() == user_manager::USER_TYPE_GUEST)
-    login_user_type = LoginState::LOGGED_IN_USER_GUEST;
-  else if (active_user_->GetType() == user_manager::USER_TYPE_RETAIL_MODE)
-    login_user_type = LoginState::LOGGED_IN_USER_RETAIL_MODE;
-  else if (active_user_->GetType() == user_manager::USER_TYPE_PUBLIC_ACCOUNT)
-    login_user_type = LoginState::LOGGED_IN_USER_PUBLIC_ACCOUNT;
-  else if (active_user_->GetType() == user_manager::USER_TYPE_SUPERVISED)
-    login_user_type = LoginState::LOGGED_IN_USER_SUPERVISED;
-  else if (active_user_->GetType() == user_manager::USER_TYPE_KIOSK_APP)
-    login_user_type = LoginState::LOGGED_IN_USER_KIOSK_APP;
+    login_user_type = chromeos::LoginState::LOGGED_IN_USER_OWNER;
+  else if (active_user_->GetType() == USER_TYPE_GUEST)
+    login_user_type = chromeos::LoginState::LOGGED_IN_USER_GUEST;
+  else if (active_user_->GetType() == USER_TYPE_RETAIL_MODE)
+    login_user_type = chromeos::LoginState::LOGGED_IN_USER_RETAIL_MODE;
+  else if (active_user_->GetType() == USER_TYPE_PUBLIC_ACCOUNT)
+    login_user_type = chromeos::LoginState::LOGGED_IN_USER_PUBLIC_ACCOUNT;
+  else if (active_user_->GetType() == USER_TYPE_SUPERVISED)
+    login_user_type = chromeos::LoginState::LOGGED_IN_USER_SUPERVISED;
+  else if (active_user_->GetType() == USER_TYPE_KIOSK_APP)
+    login_user_type = chromeos::LoginState::LOGGED_IN_USER_KIOSK_APP;
   else
-    login_user_type = LoginState::LOGGED_IN_USER_REGULAR;
+    login_user_type = chromeos::LoginState::LOGGED_IN_USER_REGULAR;
 
   if (primary_user_) {
-    LoginState::Get()->SetLoggedInStateAndPrimaryUser(
+    chromeos::LoginState::Get()->SetLoggedInStateAndPrimaryUser(
         logged_in_state, login_user_type, primary_user_->username_hash());
   } else {
-    LoginState::Get()->SetLoggedInState(logged_in_state, login_user_type);
+    chromeos::LoginState::Get()->SetLoggedInState(logged_in_state,
+                                                  login_user_type);
   }
 }
 
-void UserManagerBase::SetLRUUser(user_manager::User* user) {
-  user_manager::UserList::iterator it =
+void UserManagerBase::SetLRUUser(User* user) {
+  UserList::iterator it =
       std::find(lru_logged_in_users_.begin(), lru_logged_in_users_.end(), user);
   if (it != lru_logged_in_users_.end())
     lru_logged_in_users_.erase(it);
@@ -994,7 +966,7 @@ void UserManagerBase::SendRegularUserLoginMetrics(const std::string& user_id) {
   // If this isn't the first time Chrome was run after the system booted,
   // assume that Chrome was restarted because a previous session ended.
   if (!CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kFirstExecAfterBoot)) {
+          chromeos::switches::kFirstExecAfterBoot)) {
     const std::string last_email =
         GetLocalState()->GetString(kLastLoggedInRegularUser);
     const base::TimeDelta time_to_login =
@@ -1017,27 +989,38 @@ void UserManagerBase::UpdateUserAccountLocale(const std::string& user_id,
         base::Bind(&UserManagerBase::DoUpdateAccountLocale,
                    weak_factory_.GetWeakPtr(),
                    user_id);
-    BrowserThread::PostBlockingPoolTask(FROM_HERE,
-                                        base::Bind(ResolveLocale,
-                                                   locale,
-                                                   on_resolve_callback));
+    blocking_task_runner_->PostTask(FROM_HERE,
+                                    base::Bind(&UserManagerBase::ResolveLocale,
+                                               weak_factory_.GetWeakPtr(),
+                                               locale,
+                                               on_resolve_callback));
   } else {
     DoUpdateAccountLocale(user_id, locale);
   }
 }
 
+void UserManagerBase::ResolveLocale(
+    const std::string& raw_locale,
+    base::Callback<void(const std::string&)> on_resolve_callback) {
+  DCHECK(task_runner_->RunsTasksOnCurrentThread());
+  std::string resolved_locale;
+  ignore_result(l10n_util::CheckAndResolveLocale(raw_locale, &resolved_locale));
+  task_runner_->PostTask(FROM_HERE,
+                         base::Bind(on_resolve_callback, resolved_locale));
+}
+
 void UserManagerBase::DoUpdateAccountLocale(
     const std::string& user_id,
     const std::string& resolved_locale) {
-  if (user_manager::User* user = FindUserAndModify(user_id))
+  if (User* user = FindUserAndModify(user_id))
     user->SetAccountLocale(resolved_locale);
 }
 
-void UserManagerBase::DeleteUser(user_manager::User* user) {
+void UserManagerBase::DeleteUser(User* user) {
   const bool is_active_user = (user == active_user_);
   delete user;
   if (is_active_user)
     active_user_ = NULL;
 }
 
-}  // namespace chromeos
+}  // namespace user_manager
diff --git a/chrome/browser/chromeos/login/users/user_manager_base.h b/components/user_manager/user_manager_base.h
index 5fcea54..e7651cb 100644
--- a/chrome/browser/chromeos/login/users/user_manager_base.h
+++ b/components/user_manager/user_manager_base.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_BROWSER_CHROMEOS_LOGIN_USERS_USER_MANAGER_BASE_H_
-#define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_USER_MANAGER_BASE_H_
+#ifndef COMPONENTS_USER_MANAGER_USER_MANAGER_BASE_H_
+#define COMPONENTS_USER_MANAGER_USER_MANAGER_BASE_H_
 
 #include <set>
 #include <string>
@@ -14,19 +14,27 @@
 #include "base/observer_list.h"
 #include "base/synchronization/lock.h"
 #include "base/time/time.h"
-#include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_manager.h"
+#include "components/user_manager/user_manager_export.h"
 
 class PrefService;
 class PrefRegistrySimple;
 
-namespace chromeos {
+namespace base {
+class ListValue;
+class TaskRunner;
+}
+
+namespace user_manager {
 
 class RemoveUserDelegate;
 
 // Base implementation of the UserManager interface.
-class UserManagerBase : public UserManager {
+class USER_MANAGER_EXPORT UserManagerBase : public UserManager {
  public:
+  UserManagerBase(scoped_refptr<base::TaskRunner> task_runner,
+                  scoped_refptr<base::TaskRunner> blocking_task_runner);
   virtual ~UserManagerBase();
 
   // Registers UserManagerBase preferences.
@@ -34,9 +42,9 @@ class UserManagerBase : public UserManager {
 
   // UserManager implementation:
   virtual void Shutdown() OVERRIDE;
-  virtual const user_manager::UserList& GetUsers() const OVERRIDE;
-  virtual const user_manager::UserList& GetLoggedInUsers() const OVERRIDE;
-  virtual const user_manager::UserList& GetLRULoggedInUsers() const OVERRIDE;
+  virtual const UserList& GetUsers() const OVERRIDE;
+  virtual const UserList& GetLoggedInUsers() const OVERRIDE;
+  virtual const UserList& GetLRULoggedInUsers() const OVERRIDE;
   virtual const std::string& GetOwnerEmail() const OVERRIDE;
   virtual void UserLoggedIn(const std::string& user_id,
                             const std::string& user_id_hash,
@@ -47,18 +55,16 @@ class UserManagerBase : public UserManager {
                           RemoveUserDelegate* delegate) OVERRIDE;
   virtual void RemoveUserFromList(const std::string& user_id) OVERRIDE;
   virtual bool IsKnownUser(const std::string& user_id) const OVERRIDE;
-  virtual const user_manager::User* FindUser(
-      const std::string& user_id) const OVERRIDE;
-  virtual user_manager::User* FindUserAndModify(
-      const std::string& user_id) OVERRIDE;
-  virtual const user_manager::User* GetLoggedInUser() const OVERRIDE;
-  virtual user_manager::User* GetLoggedInUser() OVERRIDE;
-  virtual const user_manager::User* GetActiveUser() const OVERRIDE;
-  virtual user_manager::User* GetActiveUser() OVERRIDE;
-  virtual const user_manager::User* GetPrimaryUser() const OVERRIDE;
+  virtual const User* FindUser(const std::string& user_id) const OVERRIDE;
+  virtual User* FindUserAndModify(const std::string& user_id) OVERRIDE;
+  virtual const User* GetLoggedInUser() const OVERRIDE;
+  virtual User* GetLoggedInUser() OVERRIDE;
+  virtual const User* GetActiveUser() const OVERRIDE;
+  virtual User* GetActiveUser() OVERRIDE;
+  virtual const User* GetPrimaryUser() const OVERRIDE;
   virtual void SaveUserOAuthStatus(
       const std::string& user_id,
-      user_manager::User::OAuthTokenStatus oauth_token_status) OVERRIDE;
+      User::OAuthTokenStatus oauth_token_status) OVERRIDE;
   virtual void SaveForceOnlineSignin(const std::string& user_id,
                                      bool force_online_signin) OVERRIDE;
   virtual void SaveUserDisplayName(const std::string& user_id,
@@ -108,18 +114,18 @@ class UserManagerBase : public UserManager {
 
   // Adds |user| to users list, and adds it to front of LRU list. It is assumed
   // that there is no user with same id.
-  virtual void AddUserRecord(user_manager::User* user);
+  virtual void AddUserRecord(User* user);
 
   // Returns true if trusted device policies have successfully been retrieved
   // and ephemeral users are enabled.
   virtual bool AreEphemeralUsersEnabled() const = 0;
 
   // Returns true if user may be removed.
-  virtual bool CanUserBeRemoved(const user_manager::User* user) const;
+  virtual bool CanUserBeRemoved(const User* user) const;
 
   // A wrapper around C++ delete operator. Deletes |user|, and when |user|
   // equals to active_user_, active_user_ is reset to NULL.
-  virtual void DeleteUser(user_manager::User* user);
+  virtual void DeleteUser(User* user);
 
   // Returns the locale used by the application.
   virtual const std::string& GetApplicationLocale() const = 0;
@@ -131,6 +137,11 @@ class UserManagerBase : public UserManager {
   // Subsequent calls have no effect. Must be called on the UI thread.
   void EnsureUsersLoaded();
 
+  // Handle OAuth token |status| change for |user_id|.
+  virtual void HandleUserOAuthTokenStatusChange(
+      const std::string& user_id,
+      User::OAuthTokenStatus status) const = 0;
+
   // Returns true if device is enterprise managed.
   virtual bool IsEnterpriseManaged() const = 0;
 
@@ -148,7 +159,7 @@ class UserManagerBase : public UserManager {
   // Notifies observers that another user was added to the session.
   // If |user_switch_pending| is true this means that user has not been fully
   // initialized yet like waiting for profile to be loaded.
-  virtual void NotifyUserAddedToSession(const user_manager::User* added_user,
+  virtual void NotifyUserAddedToSession(const User* added_user,
                                         bool user_switch_pending);
 
   // Performs any additional actions before user list is loaded.
@@ -171,8 +182,7 @@ class UserManagerBase : public UserManager {
   // Removes a regular or supervised user from the user list.
   // Returns the user if found or NULL otherwise.
   // Also removes the user from the persistent user list.
-  user_manager::User* RemoveRegularOrSupervisedUserFromList(
-      const std::string& user_id);
+  User* RemoveRegularOrSupervisedUserFromList(const std::string& user_id);
 
   // Implementation for RemoveUser method. This is an asynchronous part of the
   // method, that verifies that owner will not get deleted, and calls
@@ -209,7 +219,7 @@ class UserManagerBase : public UserManager {
   virtual void KioskAppLoggedIn(const std::string& app_id) = 0;
 
   // Indicates that a user just logged into a public session.
-  virtual void PublicAccountUserLoggedIn(user_manager::User* user) = 0;
+  virtual void PublicAccountUserLoggedIn(User* user) = 0;
 
   // Indicates that a regular user just logged in.
   virtual void RegularUserLoggedIn(const std::string& user_id);
@@ -241,16 +251,16 @@ class UserManagerBase : public UserManager {
   // NULL until a user has logged in, then points to one
   // of the User instances in |users_|, the |guest_user_| instance or an
   // ephemeral user instance.
-  user_manager::User* active_user_;
+  User* active_user_;
 
   // The primary user of the current session. It is recorded for the first
   // signed-in user and does not change thereafter.
-  user_manager::User* primary_user_;
+  User* primary_user_;
 
   // List of all known users. User instances are owned by |this|. Regular users
   // are removed by |RemoveUserFromList|, public accounts by
   // |UpdateAndCleanUpPublicAccounts|.
-  user_manager::UserList users_;
+  UserList users_;
 
  private:
   // Stages of loading user list from preferences. Some methods can have
@@ -259,22 +269,21 @@ class UserManagerBase : public UserManager {
 
   // Returns a list of users who have logged into this device previously.
   // Same as GetUsers but used if you need to modify User from that list.
-  user_manager::UserList& GetUsersAndModify();
+  UserList& GetUsersAndModify();
 
   // Returns the user with the given email address if found in the persistent
   // list. Returns |NULL| otherwise.
-  const user_manager::User* FindUserInList(const std::string& user_id) const;
+  const User* FindUserInList(const std::string& user_id) const;
 
   // Returns |true| if user with the given id is found in the persistent list.
   // Returns |false| otherwise. Does not trigger user loading.
   const bool UserExistsInList(const std::string& user_id) const;
 
   // Same as FindUserInList but returns non-const pointer to User object.
-  user_manager::User* FindUserInListAndModify(const std::string& user_id);
+  User* FindUserInListAndModify(const std::string& user_id);
 
   // Reads user's oauth token status from local state preferences.
-  user_manager::User::OAuthTokenStatus LoadUserOAuthStatus(
-      const std::string& user_id) const;
+  User::OAuthTokenStatus LoadUserOAuthStatus(const std::string& user_id) const;
 
   // Read a flag indicating whether online authentication against GAIA should
   // be enforced during the user's next sign-in from local state preferences.
@@ -284,7 +293,7 @@ class UserManagerBase : public UserManager {
   void NotifyMergeSessionStateChanged();
 
   // Notifies observers that active user has changed.
-  void NotifyActiveUserChanged(const user_manager::User* active_user);
+  void NotifyActiveUserChanged(const User* active_user);
 
   // Notifies observers that active user_id hash has changed.
   void NotifyActiveUserHashChanged(const std::string& hash);
@@ -293,7 +302,7 @@ class UserManagerBase : public UserManager {
   void UpdateLoginState();
 
   // Insert |user| at the front of the LRU user list.
-  void SetLRUUser(user_manager::User* user);
+  void SetLRUUser(User* user);
 
   // Sends metrics in response to a regular user logging in.
   void SendRegularUserLoginMetrics(const std::string& user_id);
@@ -302,6 +311,12 @@ class UserManagerBase : public UserManager {
   virtual void UpdateUserAccountLocale(const std::string& user_id,
                                        const std::string& locale);
 
+  // Runs on SequencedWorkerPool thread. Passes resolved locale to
+  // |on_resolve_callback| on UI thread.
+  void ResolveLocale(
+      const std::string& raw_locale,
+      base::Callback<void(const std::string&)> on_resolve_callback);
+
   // Updates user account after locale was resolved.
   void DoUpdateAccountLocale(const std::string& user_id,
                              const std::string& resolved_locale);
@@ -311,12 +326,12 @@ class UserManagerBase : public UserManager {
 
   // List of all users that are logged in current session. These point to User
   // instances in |users_|. Only one of them could be marked as active.
-  user_manager::UserList logged_in_users_;
+  UserList logged_in_users_;
 
   // A list of all users that are logged in the current session. In contrast to
   // |logged_in_users|, the order of this list is least recently used so that
   // the active user should always be the first one in the list.
-  user_manager::UserList lru_logged_in_users_;
+  UserList lru_logged_in_users_;
 
   // True if SessionStarted() has been called.
   bool session_started_;
@@ -359,11 +374,14 @@ class UserManagerBase : public UserManager {
   // as soon as user's profile is loaded.
   std::string pending_user_switch_;
 
+  scoped_refptr<base::TaskRunner> task_runner_;
+  scoped_refptr<base::TaskRunner> blocking_task_runner_;
+
   base::WeakPtrFactory<UserManagerBase> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(UserManagerBase);
 };
 
-}  // namespace chromeos
+}  // namespace user_manager
 
-#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_USER_MANAGER_BASE_H_
+#endif  // COMPONENTS_USER_MANAGER_USER_MANAGER_BASE_H_
diff --git a/extensions/shell/browser/shell_browser_main_parts.cc b/extensions/shell/browser/shell_browser_main_parts.cc
index 3a33566..4ab9360 100644
--- a/extensions/shell/browser/shell_browser_main_parts.cc
+++ b/extensions/shell/browser/shell_browser_main_parts.cc
@@ -92,7 +92,7 @@ void ShellBrowserMainParts::PreMainMessageLoopRun() {
   desktop_controller_->CreateRootWindow();
 
   // NOTE: Much of this is culled from chrome/test/base/chrome_test_suite.cc
-  // TODO(jamescook): Initialize chromeos::UserManager.
+  // TODO(jamescook): Initialize user_manager::UserManager.
   net_log_.reset(new content::ShellNetLog("app_shell"));
 
   extensions_client_.reset(new ShellExtensionsClient());
author	nkostylev@chromium.org <nkostylev@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>	2014-08-15 09:22:58 +0000
committer	nkostylev@chromium.org <nkostylev@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>	2014-08-15 09:22:58 +0000
commit	b96c9db0b4ac10bf24c220149c074b5f27fe4a4f (patch)
tree	305014dd85fd28832ebc1b5acda4865747583241
parent	861bdb5554f52e520b302280f5fa0db14e74d9f7 (diff)
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