Revert 57749 - Disable background mode when associated pref changes.

Disabling because new tests don't work now that BackgroundModeManager is
disabled by default from r57713.

BUG=53173
TEST=new BackgroundModeManager unit tests

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=57642

Review URL: http://codereview.chromium.org/3205008

TBR=atwilson@chromium.org
Review URL: http://codereview.chromium.org/3223008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@57752 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 12 insertions, 122 deletions

diff --git a/chrome/browser/background_mode_manager.cc b/chrome/browser/background_mode_manager.cc
index 7c5a4e2..4fe5e2e 100644
--- a/chrome/browser/background_mode_manager.cc
+++ b/chrome/browser/background_mode_manager.cc
@@ -34,7 +34,6 @@
 BackgroundModeManager::BackgroundModeManager(Profile* profile)
     : profile_(profile),
       background_app_count_(0),
-      in_background_mode_(false),
       status_tray_(NULL),
       status_icon_(NULL) {
   // If background mode is globally disabled, just exit - don't listen for
@@ -74,20 +73,13 @@ BackgroundModeManager::BackgroundModeManager(Profile* profile)
   registrar_.Add(this, NotificationType::APP_TERMINATING,
                  NotificationService::AllSources());
 
-  // Listen for changes to the background mode preference.
-  profile_->GetPrefs()->AddPrefObserver(prefs::kBackgroundModeEnabled, this);
+
 }
 
 BackgroundModeManager::~BackgroundModeManager() {
-  // We're going away, so exit background mode (does nothing if we aren't in
-  // background mode currently). This is primarily needed for unit tests,
-  // because in an actual running system we'd get an APP_TERMINATING
-  // notification before being destroyed.
-  EndBackgroundMode();
-  // Manually remove our pref observer so we don't get notified for prefs
-  // changes (have to do it manually because we can't use the registrar for
-  // prefs notifications).
-  profile_->GetPrefs()->RemovePrefObserver(prefs::kBackgroundModeEnabled, this);
+  // If we're going away, remove our status tray icon so we don't get any events
+  // from it.
+  RemoveStatusTrayIcon();
 }
 
 bool BackgroundModeManager::IsBackgroundModeEnabled() {
@@ -133,18 +125,14 @@ void BackgroundModeManager::Observe(NotificationType type,
         OnBackgroundAppUninstalled();
       break;
     case NotificationType::APP_TERMINATING:
-      // Performing an explicit shutdown, so exit background mode (does nothing
-      // if we aren't in background mode currently).
-      EndBackgroundMode();
+      // Performing an explicit shutdown, so exit background mode if we were in
+      // background mode.
+      if (background_app_count_ > 0 && IsBackgroundModeEnabled())
+        EndBackgroundMode();
       // Shutting down, so don't listen for any more notifications so we don't
       // try to re-enter/exit background mode again.
       registrar_.RemoveAll();
       break;
-    case NotificationType::PREF_CHANGED:
-      DCHECK(0 == Details<std::string>(details).ptr()->compare(
-          prefs::kBackgroundModeEnabled));
-      OnBackgroundModePrefChanged();
-      break;
     default:
       NOTREACHED();
       break;
@@ -155,24 +143,6 @@ bool BackgroundModeManager::IsBackgroundApp(Extension* extension) {
   return extension->HasApiPermission(Extension::kBackgroundPermission);
 }
 
-
-void BackgroundModeManager::OnBackgroundModePrefChanged() {
-  // Background mode has been enabled/disabled in preferences, so update our
-  // state accordingly.
-  if (IsBackgroundModeEnabled() && !in_background_mode_ &&
-      background_app_count_ > 0) {
-    // We should be in background mode, but we're not, so switch to background
-    // mode.
-    EnableLaunchOnStartup(true);
-    StartBackgroundMode();
-  }
-  if (!IsBackgroundModeEnabled() && in_background_mode_) {
-    // We're in background mode, but we shouldn't be any longer.
-    EnableLaunchOnStartup(false);
-    EndBackgroundMode();
-  }
-}
-
 void BackgroundModeManager::OnBackgroundAppLoaded() {
   // When a background app loads, increment our count and also enable
   // KeepAlive mode if the preference is set.
@@ -182,13 +152,6 @@ void BackgroundModeManager::OnBackgroundAppLoaded() {
 }
 
 void BackgroundModeManager::StartBackgroundMode() {
-  // Don't bother putting ourselves in background mode if we're already there.
-  if (in_background_mode_)
-    return;
-
-  // Mark ourselves as running in background mode.
-  in_background_mode_ = true;
-
   // Put ourselves in KeepAlive mode and create a status tray icon.
   BrowserList::StartKeepAlive();
 
@@ -200,16 +163,12 @@ void BackgroundModeManager::OnBackgroundAppUnloaded() {
   // When a background app unloads, decrement our count and also end
   // KeepAlive mode if appropriate.
   background_app_count_--;
-  DCHECK(background_app_count_ >= 0);
+  DCHECK(background_app_count_ == 0);
   if (background_app_count_ == 0 && IsBackgroundModeEnabled())
     EndBackgroundMode();
 }
 
 void BackgroundModeManager::EndBackgroundMode() {
-  if (!in_background_mode_)
-    return;
-  in_background_mode_ = false;
-
   // End KeepAlive mode and blow away our status tray icon.
   BrowserList::EndKeepAlive();
   RemoveStatusTrayIcon();
diff --git a/chrome/browser/background_mode_manager.h b/chrome/browser/background_mode_manager.h
index 9970391..38b010c 100644
--- a/chrome/browser/background_mode_manager.h
+++ b/chrome/browser/background_mode_manager.h
@@ -49,12 +49,6 @@ class BackgroundModeManager
                            BackgroundAppLoadUnload);
   FRIEND_TEST_ALL_PREFIXES(BackgroundModeManagerTest,
                            BackgroundAppInstallUninstall);
-  FRIEND_TEST_ALL_PREFIXES(BackgroundModeManagerTest,
-                           BackgroundPrefDisabled);
-  FRIEND_TEST_ALL_PREFIXES(BackgroundModeManagerTest,
-                           BackgroundPrefDynamicDisable);
-  FRIEND_TEST_ALL_PREFIXES(BackgroundModeManagerTest,
-                           BackgroundPrefDynamicEnable);
 
   // NotificationObserver implementation.
   virtual void Observe(NotificationType type,
@@ -82,9 +76,6 @@ class BackgroundModeManager
   // launch-on-startup is disabled if appropriate.
   void OnBackgroundAppUninstalled();
 
-  // Invoked when the kBackgroundModeEnabled preference has changed.
-  void OnBackgroundModePrefChanged();
-
   // Returns true if the passed extension is a background app.
   bool IsBackgroundApp(Extension* extension);
 
@@ -130,11 +121,6 @@ class BackgroundModeManager
   // The number of background apps currently loaded.
   int background_app_count_;
 
-  // Set to true when we are running in background mode. Allows us to track our
-  // current background state so we can take the appropriate action when the
-  // user disables/enables background mode via preferences.
-  bool in_background_mode_;
-
   // Reference to our status tray (owned by our parent profile). If null, the
   // platform doesn't support status icons.
   StatusTray* status_tray_;
diff --git a/chrome/browser/background_mode_manager_unittest.cc b/chrome/browser/background_mode_manager_unittest.cc
index f028c7c..087b4fe 100644
--- a/chrome/browser/background_mode_manager_unittest.cc
+++ b/chrome/browser/background_mode_manager_unittest.cc
@@ -4,14 +4,10 @@
 
 #include "chrome/browser/background_mode_manager.h"
 #include "chrome/browser/browser_list.h"
-#include "chrome/browser/prefs/pref_service.h"
-#include "chrome/common/pref_names.h"
 #include "chrome/test/testing_profile.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
-using testing::InSequence;
-
 class TestBackgroundModeManager : public BackgroundModeManager {
  public:
   explicit TestBackgroundModeManager(Profile* profile)
@@ -23,79 +19,28 @@ class TestBackgroundModeManager : public BackgroundModeManager {
 };
 
 TEST(BackgroundModeManagerTest, BackgroundAppLoadUnload) {
-  InSequence s;
   TestingProfile profile;
   TestBackgroundModeManager manager(&profile);
-  EXPECT_CALL(manager, CreateStatusTrayIcon());
-  EXPECT_CALL(manager, RemoveStatusTrayIcon());
   EXPECT_FALSE(BrowserList::WillKeepAlive());
   // Call to AppLoaded() will cause the status tray to be created, then call to
   // unloaded will result in call to remove the icon.
+  EXPECT_CALL(manager, CreateStatusTrayIcon());
   manager.OnBackgroundAppLoaded();
   EXPECT_TRUE(BrowserList::WillKeepAlive());
+  EXPECT_CALL(manager, RemoveStatusTrayIcon());
   manager.OnBackgroundAppUnloaded();
   EXPECT_FALSE(BrowserList::WillKeepAlive());
 }
 
 TEST(BackgroundModeManagerTest, BackgroundAppInstallUninstall) {
-  InSequence s;
   TestingProfile profile;
   TestBackgroundModeManager manager(&profile);
   // Call to AppInstalled() will cause chrome to be set to launch on startup,
   // and call to AppUninstalling() set chrome to not launch on startup.
   EXPECT_CALL(manager, EnableLaunchOnStartup(true));
-  EXPECT_CALL(manager, CreateStatusTrayIcon());
-  EXPECT_CALL(manager, EnableLaunchOnStartup(false));
-  EXPECT_CALL(manager, RemoveStatusTrayIcon());
-  manager.OnBackgroundAppInstalled();
-  manager.OnBackgroundAppLoaded();
-  manager.OnBackgroundAppUninstalled();
-  manager.OnBackgroundAppUnloaded();
-}
-
-TEST(BackgroundModeManagerTest, BackgroundPrefDisabled) {
-  InSequence s;
-  TestingProfile profile;
-  profile.GetPrefs()->SetBoolean(prefs::kBackgroundModeEnabled, false);
-  TestBackgroundModeManager manager(&profile);
-  // Should not change launch on startup status when installing/uninstalling
-  // if background mode is disabled.
-  EXPECT_CALL(manager, EnableLaunchOnStartup(true)).Times(0);
-  EXPECT_CALL(manager, CreateStatusTrayIcon()).Times(0);
   manager.OnBackgroundAppInstalled();
   manager.OnBackgroundAppLoaded();
-  EXPECT_FALSE(BrowserList::WillKeepAlive());
+  EXPECT_CALL(manager, EnableLaunchOnStartup(false));
   manager.OnBackgroundAppUninstalled();
   manager.OnBackgroundAppUnloaded();
 }
-
-TEST(BackgroundModeManagerTest, BackgroundPrefDynamicDisable) {
-  InSequence s;
-  TestingProfile profile;
-  TestBackgroundModeManager manager(&profile);
-  EXPECT_CALL(manager, EnableLaunchOnStartup(true));
-  EXPECT_CALL(manager, CreateStatusTrayIcon());
-  EXPECT_CALL(manager, EnableLaunchOnStartup(false));
-  EXPECT_CALL(manager, RemoveStatusTrayIcon());
-  manager.OnBackgroundAppInstalled();
-  manager.OnBackgroundAppLoaded();
-  EXPECT_TRUE(BrowserList::WillKeepAlive());
-  // Disable status on the fly.
-  profile.GetPrefs()->SetBoolean(prefs::kBackgroundModeEnabled, false);
-  EXPECT_FALSE(BrowserList::WillKeepAlive());
-}
-
-TEST(BackgroundModeManagerTest, BackgroundPrefDynamicEnable) {
-  InSequence s;
-  TestingProfile profile;
-  TestBackgroundModeManager manager(&profile);
-  profile.GetPrefs()->SetBoolean(prefs::kBackgroundModeEnabled, false);
-  EXPECT_CALL(manager, EnableLaunchOnStartup(true));
-  EXPECT_CALL(manager, CreateStatusTrayIcon());
-  manager.OnBackgroundAppInstalled();
-  manager.OnBackgroundAppLoaded();
-  EXPECT_FALSE(BrowserList::WillKeepAlive());
-  // Enable status on the fly.
-  profile.GetPrefs()->SetBoolean(prefs::kBackgroundModeEnabled, true);
-  EXPECT_TRUE(BrowserList::WillKeepAlive());
-}