Don't use base::MessageLoop::{Quit,QuitClosure} in chrome/

This patch renames base::MessageLoop::{Quit,QuitClosure} to
base::MessageLoop::{QuitWhenIdle,QuitWhenIdleClosure}.

BUG=131220
TEST=
R=thestig@chromium.org

Review URL: https://codereview.chromium.org/1395103003

Cr-Commit-Position: refs/heads/master@{#353376}

153 files changed, 326 insertions, 350 deletions

diff --git a/chrome/browser/app_controller_mac_browsertest.mm b/chrome/browser/app_controller_mac_browsertest.mm
index c304151..591ac50 100644
--- a/chrome/browser/app_controller_mac_browsertest.mm
+++ b/chrome/browser/app_controller_mac_browsertest.mm
@@ -218,7 +218,7 @@ void CreateProfileCallback(const base::Closure& quit_closure,
 void CreateAndWaitForSystemProfile() {
   ProfileManager::CreateCallback create_callback =
       base::Bind(&CreateProfileCallback,
-                 base::MessageLoop::current()->QuitClosure());
+                 base::MessageLoop::current()->QuitWhenIdleClosure());
   g_browser_process->profile_manager()->CreateProfileAsync(
       ProfileManager::GetSystemProfilePath(),
       create_callback,
diff --git a/chrome/browser/apps/app_window_browsertest.cc b/chrome/browser/apps/app_window_browsertest.cc
index 80765dc..f498e37 100644
--- a/chrome/browser/apps/app_window_browsertest.cc
+++ b/chrome/browser/apps/app_window_browsertest.cc
@@ -61,7 +61,7 @@ class GeometryCacheChangeHelper : AppWindowGeometryCache::Observer {
       cache_->RemoveObserver(this);
 
       if (waiting_)
-        base::MessageLoopForUI::current()->Quit();
+        base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/apps/ephemeral_app_launcher_browsertest.cc b/chrome/browser/apps/ephemeral_app_launcher_browsertest.cc
index 63e6bc9..fbeb7f8 100644
--- a/chrome/browser/apps/ephemeral_app_launcher_browsertest.cc
+++ b/chrome/browser/apps/ephemeral_app_launcher_browsertest.cc
@@ -150,7 +150,7 @@ class LaunchObserver {
     done_ = true;
     if (waiting_) {
       waiting_ = false;
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/autocomplete/autocomplete_provider_unittest.cc b/chrome/browser/autocomplete/autocomplete_provider_unittest.cc
index 68f80f6..3c876a2 100644
--- a/chrome/browser/autocomplete/autocomplete_provider_unittest.cc
+++ b/chrome/browser/autocomplete/autocomplete_provider_unittest.cc
@@ -507,7 +507,7 @@ void AutocompleteProviderTest::Observe(
     const content::NotificationDetails& details) {
   if (controller_->done()) {
     CopyResults();
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 }
 
diff --git a/chrome/browser/autocomplete/history_quick_provider_unittest.cc b/chrome/browser/autocomplete/history_quick_provider_unittest.cc
index dd9d840..e554276 100644
--- a/chrome/browser/autocomplete/history_quick_provider_unittest.cc
+++ b/chrome/browser/autocomplete/history_quick_provider_unittest.cc
@@ -168,7 +168,7 @@ class GetURLTask : public history::HistoryDBTask {
   }
 
   void DoneRunOnMainThread() override {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
  private:
diff --git a/chrome/browser/autocomplete/history_url_provider_unittest.cc b/chrome/browser/autocomplete/history_url_provider_unittest.cc
index c8e4847..f904c91 100644
--- a/chrome/browser/autocomplete/history_url_provider_unittest.cc
+++ b/chrome/browser/autocomplete/history_url_provider_unittest.cc
@@ -248,7 +248,7 @@ class HistoryURLProviderTestNoSearchProvider : public HistoryURLProviderTest {
 
 void HistoryURLProviderTest::OnProviderUpdate(bool updated_matches) {
   if (autocomplete_->done())
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
 }
 
 bool HistoryURLProviderTest::SetUpImpl(bool no_db) {
diff --git a/chrome/browser/autocomplete/shortcuts_backend_unittest.cc b/chrome/browser/autocomplete/shortcuts_backend_unittest.cc
index 4ac93bc..1ccc1b5 100644
--- a/chrome/browser/autocomplete/shortcuts_backend_unittest.cc
+++ b/chrome/browser/autocomplete/shortcuts_backend_unittest.cc
@@ -136,7 +136,7 @@ void ShortcutsBackendTest::TearDown() {
 
 void ShortcutsBackendTest::OnShortcutsLoaded() {
   load_notified_ = true;
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void ShortcutsBackendTest::OnShortcutsChanged() {
diff --git a/chrome/browser/autofill/autofill_browsertest.cc b/chrome/browser/autofill/autofill_browsertest.cc
index ecd5e80..a298a6e 100644
--- a/chrome/browser/autofill/autofill_browsertest.cc
+++ b/chrome/browser/autofill/autofill_browsertest.cc
@@ -97,7 +97,7 @@ class WindowedPersonalDataManagerObserver
   // PersonalDataManagerObserver:
   void OnPersonalDataChanged() override {
     if (has_run_message_loop_) {
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
       has_run_message_loop_ = false;
     }
     alerted_ = true;
diff --git a/chrome/browser/autofill/autofill_uitest_util.cc b/chrome/browser/autofill/autofill_uitest_util.cc
index 85e560d..f220408 100644
--- a/chrome/browser/autofill/autofill_uitest_util.cc
+++ b/chrome/browser/autofill/autofill_uitest_util.cc
@@ -43,7 +43,7 @@ class PdmChangeWaiter
   // PersonalDataManagerObserver:
   void OnPersonalDataChanged() override {
     if (has_run_message_loop_) {
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
       has_run_message_loop_ = false;
     }
     alerted_ = true;
diff --git a/chrome/browser/browser_keyevents_browsertest.cc b/chrome/browser/browser_keyevents_browsertest.cc
index d7fc76fd..31718d2 100644
--- a/chrome/browser/browser_keyevents_browsertest.cc
+++ b/chrome/browser/browser_keyevents_browsertest.cc
@@ -117,7 +117,7 @@ class TestFinishObserver : public content::NotificationObserver {
     if (*dom_op_result.ptr() == "\"FINISHED\"") {
       finished_ = true;
       if (waiting_)
-        base::MessageLoopForUI::current()->Quit();
+        base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/browser_process_impl.cc b/chrome/browser/browser_process_impl.cc
index 8d432d6..b77777e 100644
--- a/chrome/browser/browser_process_impl.cc
+++ b/chrome/browser/browser_process_impl.cc
@@ -401,7 +401,7 @@ unsigned int BrowserProcessImpl::ReleaseModule() {
         FROM_HERE,
         base::Bind(ChromeBrowserMainPartsMac::DidEndMainMessageLoop));
 #endif
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
   return module_ref_count_;
 }
diff --git a/chrome/browser/browsing_data/browsing_data_database_helper_browsertest.cc b/chrome/browser/browsing_data/browsing_data_database_helper_browsertest.cc
index c78471a..e6ddc59 100644
--- a/chrome/browser/browsing_data/browsing_data_database_helper_browsertest.cc
+++ b/chrome/browser/browsing_data/browsing_data_database_helper_browsertest.cc
@@ -72,7 +72,7 @@ class StopTestOnCallback {
     ASSERT_EQ(1UL, database_info_list.size());
     EXPECT_EQ(std::string(kTestIdentifier1),
               database_info_list.begin()->identifier.ToString());
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
  private:
diff --git a/chrome/browser/browsing_data/browsing_data_file_system_helper_unittest.cc b/chrome/browser/browsing_data/browsing_data_file_system_helper_unittest.cc
index 32a8fc2..7b57261 100644
--- a/chrome/browser/browsing_data/browsing_data_file_system_helper_unittest.cc
+++ b/chrome/browser/browsing_data/browsing_data_file_system_helper_unittest.cc
@@ -87,9 +87,7 @@ class BrowsingDataFileSystemHelperTest : public testing::Test {
 
   // Unblocks the current MessageLoop. Should be called in response to some sort
   // of async activity in a callback method.
-  void Notify() {
-    base::MessageLoop::current()->Quit();
-  }
+  void Notify() { base::MessageLoop::current()->QuitWhenIdle(); }
 
   // Callback that should be executed in response to
   // storage::FileSystemContext::OpenFileSystem.
diff --git a/chrome/browser/browsing_data/browsing_data_helper_browsertest.h b/chrome/browser/browsing_data/browsing_data_helper_browsertest.h
index 8c326c7..29a82881 100644
--- a/chrome/browser/browsing_data/browsing_data_helper_browsertest.h
+++ b/chrome/browser/browsing_data/browsing_data_helper_browsertest.h
@@ -30,7 +30,7 @@ class BrowsingDataHelperCallback {
   void callback(const std::list<T>& info) {
     result_ = info;
     has_result_ = true;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
  private:
diff --git a/chrome/browser/browsing_data/browsing_data_local_storage_helper_browsertest.cc b/chrome/browser/browsing_data/browsing_data_local_storage_helper_browsertest.cc
index 1dad27a..ae40709 100644
--- a/chrome/browser/browsing_data/browsing_data_local_storage_helper_browsertest.cc
+++ b/chrome/browser/browsing_data/browsing_data_local_storage_helper_browsertest.cc
@@ -100,7 +100,7 @@ class StopTestOnCallback {
     for (size_t i = 0; i < arraysize(kTestHosts); ++i) {
       ASSERT_TRUE(test_hosts_found[i]) << kTestHosts[i];
     }
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
  private:
diff --git a/chrome/browser/browsing_data/browsing_data_remover_unittest.cc b/chrome/browser/browsing_data/browsing_data_remover_unittest.cc
index 467596a..b3ff6a9 100644
--- a/chrome/browser/browsing_data/browsing_data_remover_unittest.cc
+++ b/chrome/browser/browsing_data/browsing_data_remover_unittest.cc
@@ -651,7 +651,7 @@ class RemoveAutofillTester : public autofill::PersonalDataManagerObserver {
 
  private:
   void OnPersonalDataChanged() override {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   autofill::PersonalDataManager* personal_data_manager_;
diff --git a/chrome/browser/captive_portal/captive_portal_browsertest.cc b/chrome/browser/captive_portal/captive_portal_browsertest.cc
index 1bca5ec..d6a50c6 100644
--- a/chrome/browser/captive_portal/captive_portal_browsertest.cc
+++ b/chrome/browser/captive_portal/captive_portal_browsertest.cc
@@ -319,7 +319,7 @@ void URLRequestTimeoutOnDemandJob::MaybeStopWaitingForJobsOnIOThread() {
     last_num_jobs_to_wait_for_ = num_jobs_to_wait_for_;
     num_jobs_to_wait_for_ = 0;
     BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
-                            base::MessageLoop::QuitClosure());
+                            base::MessageLoop::QuitWhenIdleClosure());
   }
 }
 
@@ -651,7 +651,7 @@ void MultiNavigationObserver::Observe(
   if (waiting_for_navigation_ &&
       num_navigations_to_wait_for_ == num_navigations_) {
     waiting_for_navigation_ = false;
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 }
 
@@ -741,7 +741,7 @@ void FailLoadsAfterLoginObserver::Observe(
       tabs_needing_navigation_.size() ==
           tabs_navigated_to_final_destination_.size()) {
     waiting_for_navigation_ = false;
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 }
 
@@ -835,7 +835,7 @@ void CaptivePortalObserver::Observe(
   if (waiting_for_result_ &&
       num_results_to_wait_for_ == num_results_received_) {
     waiting_for_result_ = false;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 }
 
diff --git a/chrome/browser/chromeos/customization/customization_wallpaper_downloader_browsertest.cc b/chrome/browser/chromeos/customization/customization_wallpaper_downloader_browsertest.cc
index 6a97f30..a294883 100644
--- a/chrome/browser/chromeos/customization/customization_wallpaper_downloader_browsertest.cc
+++ b/chrome/browser/chromeos/customization/customization_wallpaper_downloader_browsertest.cc
@@ -69,7 +69,7 @@ class TestWallpaperObserver : public WallpaperManager::Observer {
 
   void OnWallpaperAnimationFinished(const std::string&) override {
     finished_ = true;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void WaitForWallpaperAnimationFinished() {
diff --git a/chrome/browser/chromeos/file_manager/file_manager_browsertest_base.cc b/chrome/browser/chromeos/file_manager/file_manager_browsertest_base.cc
index 16eff75..5a2ff7e 100644
--- a/chrome/browser/chromeos/file_manager/file_manager_browsertest_base.cc
+++ b/chrome/browser/chromeos/file_manager/file_manager_browsertest_base.cc
@@ -232,7 +232,7 @@ class FileManagerTestListener : public content::NotificationObserver {
             ? content::Source<extensions::TestSendMessageFunction>(source).ptr()
             : NULL;
     messages_.push_back(entry);
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
  private:
diff --git a/chrome/browser/chromeos/input_method/input_method_engine_browsertests.cc b/chrome/browser/chromeos/input_method/input_method_engine_browsertests.cc
index be373fb..1dbc17e 100644
--- a/chrome/browser/chromeos/input_method/input_method_engine_browsertests.cc
+++ b/chrome/browser/chromeos/input_method/input_method_engine_browsertests.cc
@@ -119,7 +119,7 @@ class KeyEventDoneCallback {
 
   void Run(bool consumed) {
     if (consumed == expected_argument_) {
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
       is_called_ = true;
     }
   }
diff --git a/chrome/browser/chromeos/input_method/textinput_test_helper.cc b/chrome/browser/chromeos/input_method/textinput_test_helper.cc
index 34554d2..7a7d3a6 100644
--- a/chrome/browser/chromeos/input_method/textinput_test_helper.cc
+++ b/chrome/browser/chromeos/input_method/textinput_test_helper.cc
@@ -76,7 +76,7 @@ void TextInputTestHelper::OnTextInputTypeChanged(
   latest_text_input_type_ =
       client ? client->GetTextInputType() : ui::TEXT_INPUT_TYPE_NONE;
   if (waiting_type_ == WAIT_ON_TEXT_INPUT_TYPE_CHANGED)
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void TextInputTestHelper::OnShowImeIfNeeded() {
@@ -89,13 +89,13 @@ void TextInputTestHelper::OnInputMethodDestroyed(
 void TextInputTestHelper::OnFocus() {
   focus_state_ = true;
   if (waiting_type_ == WAIT_ON_FOCUS)
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void TextInputTestHelper::OnBlur() {
   focus_state_ = false;
   if (waiting_type_ == WAIT_ON_BLUR)
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void TextInputTestHelper::OnCaretBoundsChanged(
@@ -109,7 +109,7 @@ void TextInputTestHelper::OnCaretBoundsChanged(
       return;
   }
   if (waiting_type_ == WAIT_ON_CARET_BOUNDS_CHANGED)
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void TextInputTestHelper::OnTextInputStateChanged(
diff --git a/chrome/browser/chromeos/login/lock/screen_locker_browsertest.cc b/chrome/browser/chromeos/login/lock/screen_locker_browsertest.cc
index fb398bbf..c3bbabe 100644
--- a/chrome/browser/chromeos/login/lock/screen_locker_browsertest.cc
+++ b/chrome/browser/chromeos/login/lock/screen_locker_browsertest.cc
@@ -62,7 +62,7 @@ class Waiter : public content::NotificationObserver {
     DCHECK(type == chrome::NOTIFICATION_SCREEN_LOCK_STATE_CHANGED ||
            type == chrome::NOTIFICATION_FULLSCREEN_CHANGED);
     if (running_)
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
   }
 
   // Wait until the two conditions are met.
diff --git a/chrome/browser/chromeos/login/lock/screen_locker_tester.cc b/chrome/browser/chromeos/login/lock/screen_locker_tester.cc
index c3fc29b..2b6720b 100644
--- a/chrome/browser/chromeos/login/lock/screen_locker_tester.cc
+++ b/chrome/browser/chromeos/login/lock/screen_locker_tester.cc
@@ -82,7 +82,7 @@ void LoginAttemptObserver::WaitForAttempt() {
 void LoginAttemptObserver::LoginAttempted() {
   login_attempted_ = true;
   if (waiting_)
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
 }
 
 }  // anyonymous namespace
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 f3d283e..226ea84 100644
--- a/chrome/browser/chromeos/login/ui/login_display_host_impl.cc
+++ b/chrome/browser/chromeos/login/ui/login_display_host_impl.cc
@@ -913,7 +913,7 @@ void LoginDisplayHostImpl::ShutdownDisplayHost(bool post_quit_task) {
   registrar_.RemoveAll();
   base::MessageLoop::current()->DeleteSoon(FROM_HERE, this);
   if (post_quit_task)
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
 
   if (!completion_callback_.is_null())
     base::MessageLoop::current()->PostTask(FROM_HERE, completion_callback_);
diff --git a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc
index b655409..59eebad 100644
--- a/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc
+++ b/chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc
@@ -41,7 +41,7 @@ class TestWallpaperObserverPendingListEmpty
 
   void OnPendingListEmptyForTesting() override {
     empty_ = true;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void WaitForPendingListEmpty() {
diff --git a/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc b/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc
index 7d89c81..05c8c9e 100644
--- a/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc
+++ b/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc
@@ -206,7 +206,7 @@ class FakeClientObserver
       delegate_->FakeRegisterWithOS(worker_->protocol());
     }
     if (state != ShellIntegration::STATE_PROCESSING) {
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/devtools/device/adb/adb_client_socket_browsertest.cc b/chrome/browser/devtools/device/adb/adb_client_socket_browsertest.cc
index b0b4e5f..0f30260 100644
--- a/chrome/browser/devtools/device/adb/adb_client_socket_browsertest.cc
+++ b/chrome/browser/devtools/device/adb/adb_client_socket_browsertest.cc
@@ -41,7 +41,7 @@ class AdbClientSocketTest : public InProcessBrowserTest,
       const DevToolsAndroidBridge::RemoteDevices& devices) override {
     devices_ = devices;
     android_bridge_->RemoveDeviceListListener(this);
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void CheckDevices() {
diff --git a/chrome/browser/devtools/device/adb/mock_adb_server.cc b/chrome/browser/devtools/device/adb/mock_adb_server.cc
index 70e9a0c..3fe93df 100644
--- a/chrome/browser/devtools/device/adb/mock_adb_server.cc
+++ b/chrome/browser/devtools/device/adb/mock_adb_server.cc
@@ -601,19 +601,16 @@ void MockAndroidConnection::SendHTTPResponse(const std::string& body) {
 
 void StartMockAdbServer(FlushMode flush_mode) {
   BrowserThread::PostTaskAndReply(
-      BrowserThread::IO,
-      FROM_HERE,
+      BrowserThread::IO, FROM_HERE,
       base::Bind(&StartMockAdbServerOnIOThread, flush_mode),
-      base::MessageLoop::QuitClosure());
+      base::MessageLoop::QuitWhenIdleClosure());
   content::RunMessageLoop();
 }
 
 void StopMockAdbServer() {
-  BrowserThread::PostTaskAndReply(
-      BrowserThread::IO,
-      FROM_HERE,
-      base::Bind(&StopMockAdbServerOnIOThread),
-      base::MessageLoop::QuitClosure());
+  BrowserThread::PostTaskAndReply(BrowserThread::IO, FROM_HERE,
+                                  base::Bind(&StopMockAdbServerOnIOThread),
+                                  base::MessageLoop::QuitWhenIdleClosure());
   content::RunMessageLoop();
 }
 
diff --git a/chrome/browser/devtools/device/port_forwarding_browsertest.cc b/chrome/browser/devtools/device/port_forwarding_browsertest.cc
index e52ae72..5e2599d 100644
--- a/chrome/browser/devtools/device/port_forwarding_browsertest.cc
+++ b/chrome/browser/devtools/device/port_forwarding_browsertest.cc
@@ -62,7 +62,7 @@ class PortForwardingTest: public InProcessBrowserTest {
       if (status.empty() && skip_empty_devices_)
         return;
       base::ThreadTaskRunnerHandle::Get()->PostTask(
-          FROM_HERE, base::MessageLoop::QuitClosure());
+          FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
     }
 
     void set_skip_empty_devices(bool skip_empty_devices) {
@@ -178,9 +178,8 @@ IN_PROC_BROWSER_TEST_F(PortForwardingDisconnectTest, DisconnectOnRelease) {
 
   self_provider->set_release_callback_for_test(
       base::Bind(&base::MessageLoop::PostTask,
-                 base::Unretained(base::MessageLoop::current()),
-                 FROM_HERE,
-                 base::MessageLoop::QuitClosure()));
+                 base::Unretained(base::MessageLoop::current()), FROM_HERE,
+                 base::MessageLoop::QuitWhenIdleClosure()));
   wait_for_port_forwarding.reset();
   content::RunMessageLoop();
 }
diff --git a/chrome/browser/devtools/device/usb/android_usb_browsertest.cc b/chrome/browser/devtools/device/usb/android_usb_browsertest.cc
index 64a8c33..a01b9ac 100644
--- a/chrome/browser/devtools/device/usb/android_usb_browsertest.cc
+++ b/chrome/browser/devtools/device/usb/android_usb_browsertest.cc
@@ -641,7 +641,7 @@ class MockCountListener : public DevToolsAndroidBridge::DeviceCountListener {
     Shutdown();
   }
 
-  void Shutdown() { base::MessageLoop::current()->Quit(); }
+  void Shutdown() { base::MessageLoop::current()->QuitWhenIdle(); }
 
   DevToolsAndroidBridge* adb_bridge_;
   int invoked_;
diff --git a/chrome/browser/devtools/devtools_sanity_browsertest.cc b/chrome/browser/devtools/devtools_sanity_browsertest.cc
index e8fc89c..b547a00 100644
--- a/chrome/browser/devtools/devtools_sanity_browsertest.cc
+++ b/chrome/browser/devtools/devtools_sanity_browsertest.cc
@@ -316,7 +316,7 @@ class DevToolsUnresponsiveBeforeUnloadTest: public DevToolsBeforeUnloadTest {
 
 void TimeoutCallback(const std::string& timeout_message) {
   ADD_FAILURE() << timeout_message;
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 // Base class for DevTools tests that test devtools functionality for
@@ -400,7 +400,7 @@ class DevToolsExtensionTest : public DevToolsSanityTest,
     switch (type) {
       case extensions::NOTIFICATION_EXTENSION_LOADED_DEPRECATED:
       case extensions::NOTIFICATION_EXTENSION_HOST_DID_STOP_FIRST_LOAD:
-        base::MessageLoopForUI::current()->Quit();
+        base::MessageLoopForUI::current()->QuitWhenIdle();
         break;
       default:
         NOTREACHED();
@@ -454,7 +454,7 @@ class WorkerDevToolsSanityTest : public InProcessBrowserTest {
       worker_data_->worker_route_id = route_id;
       WorkerService::GetInstance()->RemoveObserver(this);
       BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
-          base::MessageLoop::QuitClosure());
+                              base::MessageLoop::QuitWhenIdleClosure());
       delete this;
     }
     std::string path_;
@@ -475,7 +475,7 @@ class WorkerDevToolsSanityTest : public InProcessBrowserTest {
       ASSERT_EQ(worker_data_->worker_route_id, route_id);
       WorkerService::GetInstance()->RemoveObserver(this);
       BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
-          base::MessageLoop::QuitClosure());
+                              base::MessageLoop::QuitWhenIdleClosure());
       delete this;
     }
     scoped_refptr<WorkerData> worker_data_;
@@ -521,7 +521,7 @@ class WorkerDevToolsSanityTest : public InProcessBrowserTest {
       worker_data->worker_process_id = worker_info[0].process_id;
       worker_data->worker_route_id = worker_info[0].route_id;
       BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
-          base::MessageLoop::QuitClosure());
+                              base::MessageLoop::QuitWhenIdleClosure());
       return;
     }
 
diff --git a/chrome/browser/download/download_browsertest.cc b/chrome/browser/download/download_browsertest.cc
index 9abd16f..690bf41 100644
--- a/chrome/browser/download/download_browsertest.cc
+++ b/chrome/browser/download/download_browsertest.cc
@@ -145,7 +145,7 @@ class CreatedObserver : public content::DownloadManager::Observer {
                          content::DownloadItem* item) override {
     DCHECK_EQ(manager_, manager);
     if (waiting_)
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   content::DownloadManager* manager_;
@@ -187,10 +187,10 @@ class PercentWaiter : public content::DownloadItem::Observer {
           (item_->PercentComplete() != 100)))) {
       error_ = true;
       if (waiting_)
-        base::MessageLoopForUI::current()->Quit();
+        base::MessageLoopForUI::current()->QuitWhenIdle();
     }
     if (item_->GetState() == DownloadItem::COMPLETE && waiting_)
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   void OnDownloadDestroyed(content::DownloadItem* item) override {
@@ -274,7 +274,7 @@ class DownloadsHistoryDataCollector {
       scoped_ptr<std::vector<history::DownloadRow> > entries) {
     result_valid_ = true;
     results_ = entries.Pass();
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   Profile* profile_;
@@ -298,7 +298,7 @@ class MockAbortExtensionInstallPrompt : public ExtensionInstallPrompt {
                       const Extension* extension,
                       const ShowDialogCallback& show_dialog_callback) override {
     delegate->InstallUIAbort(true);
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   void OnInstallSuccess(const Extension* extension, SkBitmap* icon) override {}
@@ -395,7 +395,7 @@ class HistoryObserver : public DownloadHistory::Observer {
 
     seen_stored_ = true;
     if (waiting_)
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   void OnDownloadHistoryDestroyed() override {
@@ -1109,8 +1109,8 @@ class DownloadTest : public InProcessBrowserTest {
   static void EnsureNoPendingDownloadJobsOnIO(bool* result) {
     if (net::URLRequestSlowDownloadJob::NumberOutstandingRequests())
       *result = false;
-    BrowserThread::PostTask(
-        BrowserThread::UI, FROM_HERE, base::MessageLoop::QuitClosure());
+    BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
+                            base::MessageLoop::QuitWhenIdleClosure());
   }
 
   // Location of the test data.
@@ -3553,7 +3553,7 @@ IN_PROC_BROWSER_TEST_F(DownloadTestWithShelf, PRE_DownloadTest_History) {
   HistoryServiceFactory::GetForProfile(browser()->profile(),
                                        ServiceAccessType::IMPLICIT_ACCESS)
       ->FlushForTest(base::Bind(
-          &base::MessageLoop::Quit,
+          &base::MessageLoop::QuitWhenIdle,
           base::Unretained(base::MessageLoop::current()->current())));
   content::RunMessageLoop();
 }
diff --git a/chrome/browser/download/save_page_browsertest.cc b/chrome/browser/download/save_page_browsertest.cc
index 67ba540..d1f0cf3 100644
--- a/chrome/browser/download/save_page_browsertest.cc
+++ b/chrome/browser/download/save_page_browsertest.cc
@@ -96,7 +96,7 @@ class DownloadPersistedObserver : public DownloadHistory::Observer {
                         const history::DownloadRow& info) override {
     persisted_ = persisted_ || filter_.Run(item, info);
     if (persisted_ && waiting_)
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
  private:
@@ -134,7 +134,7 @@ class DownloadRemovedObserver : public DownloadPersistedObserver {
   void OnDownloadsRemoved(const DownloadHistory::IdSet& ids) override {
     removed_ = ids.find(download_id_) != ids.end();
     if (removed_ && waiting_)
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
  private:
@@ -230,14 +230,14 @@ class DownloadItemCreatedObserver : public DownloadManager::Observer {
     items_seen_.push_back(item);
 
     if (waiting_)
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   void ManagerGoingDown(DownloadManager* manager) override {
     manager_->RemoveObserver(this);
     manager_ = NULL;
     if (waiting_)
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   bool waiting_;
diff --git a/chrome/browser/extensions/activity_log/activity_log_browsertest.cc b/chrome/browser/extensions/activity_log/activity_log_browsertest.cc
index 41fb708..7cfd7c0 100644
--- a/chrome/browser/extensions/activity_log/activity_log_browsertest.cc
+++ b/chrome/browser/extensions/activity_log/activity_log_browsertest.cc
@@ -42,7 +42,7 @@ class ActivityLogPrerenderTest : public ExtensionApiTest {
       scoped_ptr<std::vector<scoped_refptr<Action> > > i) {
     // This is to exit RunLoop (base::MessageLoop::current()->Run()) below
     base::ThreadTaskRunnerHandle::Get()->PostTask(
-        FROM_HERE, base::MessageLoop::QuitClosure());
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
 
     ASSERT_TRUE(i->size());
     scoped_refptr<Action> last = i->front();
diff --git a/chrome/browser/extensions/activity_log/counting_policy_unittest.cc b/chrome/browser/extensions/activity_log/counting_policy_unittest.cc
index 45ac541..51218db 100644
--- a/chrome/browser/extensions/activity_log/counting_policy_unittest.cc
+++ b/chrome/browser/extensions/activity_log/counting_policy_unittest.cc
@@ -69,10 +69,8 @@ class CountingPolicyTest : public testing::Test {
   // Wait for the task queue for the specified thread to empty.
   void WaitOnThread(const BrowserThread::ID& thread) {
     BrowserThread::PostTaskAndReply(
-        thread,
-        FROM_HERE,
-        base::Bind(&base::DoNothing),
-        base::MessageLoop::current()->QuitClosure());
+        thread, FROM_HERE, base::Bind(&base::DoNothing),
+        base::MessageLoop::current()->QuitWhenIdleClosure());
     base::MessageLoop::current()->Run();
   }
 
@@ -102,15 +100,9 @@ class CountingPolicyTest : public testing::Test {
     // checker function when results are available.  This will happen on the
     // database thread.
     policy->ReadFilteredData(
-        extension_id,
-        type,
-        api_name,
-        page_url,
-        arg_url,
-        day,
-        base::Bind(&CountingPolicyTest::CheckWrapper,
-                   checker,
-                   base::MessageLoop::current()->QuitClosure()));
+        extension_id, type, api_name, page_url, arg_url, day,
+        base::Bind(&CountingPolicyTest::CheckWrapper, checker,
+                   base::MessageLoop::current()->QuitWhenIdleClosure()));
 
     // Set up a timeout for receiving results; if we haven't received anything
     // when the timeout triggers then assume that the test is broken.
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 a96d0d3..8f969b8 100644
--- a/chrome/browser/extensions/activity_log/fullstream_ui_policy_unittest.cc
+++ b/chrome/browser/extensions/activity_log/fullstream_ui_policy_unittest.cc
@@ -92,15 +92,9 @@ class FullStreamUIPolicyTest : public testing::Test {
     // checker function when results are available.  This will happen on the
     // database thread.
     policy->ReadFilteredData(
-        extension_id,
-        type,
-        api_name,
-        page_url,
-        arg_url,
-        days_ago,
-        base::Bind(&FullStreamUIPolicyTest::CheckWrapper,
-                   checker,
-                   base::MessageLoop::current()->QuitClosure()));
+        extension_id, type, api_name, page_url, arg_url, days_ago,
+        base::Bind(&FullStreamUIPolicyTest::CheckWrapper, checker,
+                   base::MessageLoop::current()->QuitWhenIdleClosure()));
 
     // Set up a timeout for receiving results; if we haven't received anything
     // when the timeout triggers then assume that the test is broken.
@@ -935,10 +929,8 @@ TEST_F(FullStreamUIPolicyTest, CapReturns) {
 
   policy->Flush();
   BrowserThread::PostTaskAndReply(
-      BrowserThread::DB,
-      FROM_HERE,
-      base::Bind(&base::DoNothing),
-      base::MessageLoop::current()->QuitClosure());
+      BrowserThread::DB, FROM_HERE, base::Bind(&base::DoNothing),
+      base::MessageLoop::current()->QuitWhenIdleClosure());
   base::MessageLoop::current()->Run();
 
   CheckReadFilteredData(
diff --git a/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc b/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc
index 13eea4b..df3396b 100644
--- a/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc
+++ b/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc
@@ -185,7 +185,7 @@ class DownloadsEventsListener : public content::NotificationObserver {
               waiting_for_.get() &&
               new_event->Satisfies(*waiting_for_)) {
             waiting_ = false;
-            base::MessageLoopForUI::current()->Quit();
+            base::MessageLoopForUI::current()->QuitWhenIdle();
           }
           break;
         }
diff --git a/chrome/browser/extensions/api/feedback_private/feedback_browsertest.cc b/chrome/browser/extensions/api/feedback_private/feedback_browsertest.cc
index b166f4c..3ff3d1f 100644
--- a/chrome/browser/extensions/api/feedback_private/feedback_browsertest.cc
+++ b/chrome/browser/extensions/api/feedback_private/feedback_browsertest.cc
@@ -22,7 +22,7 @@
 namespace {
 
 void StopMessageLoopCallback() {
-  base::MessageLoopForUI::current()->Quit();
+  base::MessageLoopForUI::current()->QuitWhenIdle();
 }
 
 }  // namespace
diff --git a/chrome/browser/extensions/api/identity/identity_apitest.cc b/chrome/browser/extensions/api/identity/identity_apitest.cc
index a626f92..b964bc9 100644
--- a/chrome/browser/extensions/api/identity/identity_apitest.cc
+++ b/chrome/browser/extensions/api/identity/identity_apitest.cc
@@ -105,7 +105,7 @@ class SendResponseDelegate
     response_.reset(new bool);
     *response_ = success;
     if (should_post_quit_) {
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/extensions/api/notifications/notifications_apitest.cc b/chrome/browser/extensions/api/notifications/notifications_apitest.cc
index ff5ec2f..ba9fe44 100644
--- a/chrome/browser/extensions/api/notifications/notifications_apitest.cc
+++ b/chrome/browser/extensions/api/notifications/notifications_apitest.cc
@@ -68,7 +68,7 @@ class UserGestureCatcher : public content::NotificationObserver {
             .ptr()
             ->user_gesture());
     if (waiting_)
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   content::NotificationRegistrar registrar_;
diff --git a/chrome/browser/extensions/api/tab_capture/tab_capture_apitest.cc b/chrome/browser/extensions/api/tab_capture/tab_capture_apitest.cc
index 786554d..7bcba9b 100644
--- a/chrome/browser/extensions/api/tab_capture/tab_capture_apitest.cc
+++ b/chrome/browser/extensions/api/tab_capture/tab_capture_apitest.cc
@@ -437,7 +437,7 @@ IN_PROC_BROWSER_TEST_F(TabCaptureApiTest, MAYBE_TabIndicator) {
       last_media_state_ = media_state;
       if (has_changed) {
         base::ThreadTaskRunnerHandle::Get()->PostTask(
-            FROM_HERE, base::MessageLoop::QuitClosure());
+            FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
       }
     }
 
diff --git a/chrome/browser/extensions/api/tabs/tabs_test.cc b/chrome/browser/extensions/api/tabs/tabs_test.cc
index 43cd585..06e5571 100644
--- a/chrome/browser/extensions/api/tabs/tabs_test.cc
+++ b/chrome/browser/extensions/api/tabs/tabs_test.cc
@@ -832,7 +832,7 @@ class ExtensionWindowLastFocusedTest : public ExtensionTabsTest {
     // AppWindowRegistry::Observer:
     void OnAppWindowActivated(AppWindow* app_window) override {
       if (app_window_ == app_window && waiting_) {
-        base::MessageLoopForUI::current()->Quit();
+        base::MessageLoopForUI::current()->QuitWhenIdle();
         waiting_ = false;
       }
     }
@@ -864,7 +864,7 @@ class ExtensionWindowLastFocusedTest : public ExtensionTabsTest {
     void OnWidgetActivationChanged(views::Widget* widget,
                                    bool active) override {
       if (widget_ == widget && waiting_) {
-        base::MessageLoopForUI::current()->Quit();
+        base::MessageLoopForUI::current()->QuitWhenIdle();
         waiting_ = false;
       }
     }
diff --git a/chrome/browser/extensions/api/top_sites/top_sites_apitest.cc b/chrome/browser/extensions/api/top_sites/top_sites_apitest.cc
index 059bb13..17bd016 100644
--- a/chrome/browser/extensions/api/top_sites/top_sites_apitest.cc
+++ b/chrome/browser/extensions/api/top_sites/top_sites_apitest.cc
@@ -53,7 +53,7 @@ class TopSitesExtensionTest : public InProcessBrowserTest {
  private:
   void OnTopSitesAvailable(const history::MostVisitedURLList& data) {
     if (waiting_) {
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
       waiting_ = false;
     }
     top_sites_inited_ = true;
diff --git a/chrome/browser/extensions/api/web_request/web_request_api_unittest.cc b/chrome/browser/extensions/api/web_request/web_request_api_unittest.cc
index c2bc422..c263ce7 100644
--- a/chrome/browser/extensions/api/web_request/web_request_api_unittest.cc
+++ b/chrome/browser/extensions/api/web_request/web_request_api_unittest.cc
@@ -465,8 +465,8 @@ TEST_F(ExtensionWebRequestTest, SimulateChancelWhileBlocked) {
   // Extension response for OnErrorOccurred: Terminate the message loop.
   ipc_sender_.PushTask(
       base::Bind(&base::MessageLoop::PostTask,
-                 base::Unretained(base::MessageLoop::current()),
-                 FROM_HERE, base::MessageLoop::QuitClosure()));
+                 base::Unretained(base::MessageLoop::current()), FROM_HERE,
+                 base::MessageLoop::QuitWhenIdleClosure()));
 
   request->Start();
   // request->Start() will have submitted OnBeforeRequest by the time we cancel.
diff --git a/chrome/browser/extensions/api/webstore_private/webstore_private_apitest.cc b/chrome/browser/extensions/api/webstore_private/webstore_private_apitest.cc
index a304a04..6d63a6a 100644
--- a/chrome/browser/extensions/api/webstore_private/webstore_private_apitest.cc
+++ b/chrome/browser/extensions/api/webstore_private/webstore_private_apitest.cc
@@ -54,7 +54,7 @@ class WebstoreInstallListener : public WebstoreInstaller::Delegate {
 
     if (waiting_) {
       waiting_ = false;
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 
@@ -68,7 +68,7 @@ class WebstoreInstallListener : public WebstoreInstaller::Delegate {
 
     if (waiting_) {
       waiting_ = false;
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/extensions/app_data_migrator_unittest.cc b/chrome/browser/extensions/app_data_migrator_unittest.cc
index 8bb4f43..a9d1e32 100644
--- a/chrome/browser/extensions/app_data_migrator_unittest.cc
+++ b/chrome/browser/extensions/app_data_migrator_unittest.cc
@@ -105,7 +105,7 @@ void MigrationCallback() {
 }
 
 void DidWrite(base::File::Error status, int64 bytes, bool complete) {
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void DidCreate(base::File::Error status) {
@@ -183,7 +183,7 @@ void VerifyFileContents(base::File file,
   file.Close();
   if (!on_close_callback.is_null())
     on_close_callback.Run();
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void VerifyTestFilesMigrated(content::StoragePartition* new_partition,
diff --git a/chrome/browser/extensions/crx_installer_browsertest.cc b/chrome/browser/extensions/crx_installer_browsertest.cc
index f01c8f8..4656593 100644
--- a/chrome/browser/extensions/crx_installer_browsertest.cc
+++ b/chrome/browser/extensions/crx_installer_browsertest.cc
@@ -116,11 +116,11 @@ class MockInstallPrompt : public ExtensionInstallPrompt {
   }
   void OnInstallSuccess(const Extension* extension, SkBitmap* icon) override {
     proxy_->set_extension_id(extension->id());
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
   }
   void OnInstallFailure(const CrxInstallError& error) override {
     proxy_->set_error(error.message());
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
  private:
diff --git a/chrome/browser/extensions/error_console/error_console_browsertest.cc b/chrome/browser/extensions/error_console/error_console_browsertest.cc
index e55f097..b8ef787 100644
--- a/chrome/browser/extensions/error_console/error_console_browsertest.cc
+++ b/chrome/browser/extensions/error_console/error_console_browsertest.cc
@@ -158,7 +158,7 @@ class ErrorConsoleBrowserTest : public ExtensionBrowserTest {
       ++errors_observed_;
       if (errors_observed_ >= errors_expected_) {
         if (waiting_)
-          base::MessageLoopForUI::current()->Quit();
+          base::MessageLoopForUI::current()->QuitWhenIdle();
       }
     }
 
diff --git a/chrome/browser/extensions/extension_action_icon_factory_unittest.cc b/chrome/browser/extensions/extension_action_icon_factory_unittest.cc
index 3d45e15..6af5c77 100644
--- a/chrome/browser/extensions/extension_action_icon_factory_unittest.cc
+++ b/chrome/browser/extensions/extension_action_icon_factory_unittest.cc
@@ -149,7 +149,7 @@ class ExtensionActionIconFactoryTest
   // ExtensionActionIconFactory::Observer overrides:
   void OnIconUpdated() override {
     if (quit_in_icon_updated_)
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
   }
 
   gfx::ImageSkia GetFavicon() {
diff --git a/chrome/browser/extensions/extension_browsertest.cc b/chrome/browser/extensions/extension_browsertest.cc
index d264328..a510d74 100644
--- a/chrome/browser/extensions/extension_browsertest.cc
+++ b/chrome/browser/extensions/extension_browsertest.cc
@@ -389,7 +389,7 @@ class MockAbortExtensionInstallPrompt : public ExtensionInstallPrompt {
                       const Extension* extension,
                       const ShowDialogCallback& show_dialog_callback) override {
     delegate->InstallUIAbort(true);
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   void OnInstallSuccess(const Extension* extension, SkBitmap* icon) override {}
diff --git a/chrome/browser/extensions/extension_function_test_utils.cc b/chrome/browser/extensions/extension_function_test_utils.cc
index 7938d45..3dec01e 100644
--- a/chrome/browser/extensions/extension_function_test_utils.cc
+++ b/chrome/browser/extensions/extension_function_test_utils.cc
@@ -149,7 +149,7 @@ class SendResponseDelegate
     response_.reset(new bool);
     *response_ = success;
     if (should_post_quit_) {
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/extensions/extension_icon_manager_unittest.cc b/chrome/browser/extensions/extension_icon_manager_unittest.cc
index 004c196..bcec7a8 100644
--- a/chrome/browser/extensions/extension_icon_manager_unittest.cc
+++ b/chrome/browser/extensions/extension_icon_manager_unittest.cc
@@ -35,7 +35,7 @@ class ExtensionIconManagerTest : public testing::Test {
   void ImageLoadObserved() {
     unwaited_image_loads_++;
     if (waiting_) {
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/extensions/extension_service_unittest.cc b/chrome/browser/extensions/extension_service_unittest.cc
index 7935705..d22415f 100644
--- a/chrome/browser/extensions/extension_service_unittest.cc
+++ b/chrome/browser/extensions/extension_service_unittest.cc
@@ -1240,7 +1240,7 @@ void PackExtensionTestClient::OnPackSuccess(
   // on with the rest of the test.
   // This call to |Quit()| matches the call to |Run()| in the
   // |PackPunctuatedExtension| test.
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
   EXPECT_EQ(expected_crx_path_.value(), crx_path.value());
   EXPECT_EQ(expected_private_key_path_.value(), private_key_path.value());
   ASSERT_TRUE(base::PathExists(private_key_path));
@@ -4715,15 +4715,15 @@ class ExtensionCookieCallback {
 
   void SetCookieCallback(bool result) {
     base::ThreadTaskRunnerHandle::Get()->PostTask(
-        FROM_HERE,
-        base::Bind(&base::MessageLoop::Quit, weak_factory_.GetWeakPtr()));
+        FROM_HERE, base::Bind(&base::MessageLoop::QuitWhenIdle,
+                              weak_factory_.GetWeakPtr()));
     result_ = result;
   }
 
   void GetAllCookiesCallback(const net::CookieList& list) {
     base::ThreadTaskRunnerHandle::Get()->PostTask(
-        FROM_HERE,
-        base::Bind(&base::MessageLoop::Quit, weak_factory_.GetWeakPtr()));
+        FROM_HERE, base::Bind(&base::MessageLoop::QuitWhenIdle,
+                              weak_factory_.GetWeakPtr()));
     list_ = list;
   }
   net::CookieList list_;
diff --git a/chrome/browser/extensions/extension_storage_monitor_browsertest.cc b/chrome/browser/extensions/extension_storage_monitor_browsertest.cc
index 295331d..1865a13 100644
--- a/chrome/browser/extensions/extension_storage_monitor_browsertest.cc
+++ b/chrome/browser/extensions/extension_storage_monitor_browsertest.cc
@@ -64,7 +64,7 @@ class NotificationObserver : public message_center::MessageCenterObserver {
     received_notifications_.insert(notification_id);
 
     if (waiting_ && HasReceivedNotification())
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   message_center::MessageCenter* message_center_;
diff --git a/chrome/browser/extensions/extension_user_script_loader_unittest.cc b/chrome/browser/extensions/extension_user_script_loader_unittest.cc
index 02de781..b343026 100644
--- a/chrome/browser/extensions/extension_user_script_loader_unittest.cc
+++ b/chrome/browser/extensions/extension_user_script_loader_unittest.cc
@@ -71,7 +71,7 @@ class ExtensionUserScriptLoaderTest : public testing::Test,
 
     shared_memory_ = content::Details<base::SharedMemory>(details).ptr();
     if (base::MessageLoop::current() == &message_loop_)
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
   }
 
   // Directory containing user scripts.
@@ -97,8 +97,8 @@ TEST_F(ExtensionUserScriptLoaderTest, NoScripts) {
       HostID(),
       true /* listen_for_extension_system_loaded */);
   loader.StartLoad();
-  message_loop_.task_runner()->PostTask(FROM_HERE,
-                                        base::MessageLoop::QuitClosure());
+  message_loop_.task_runner()->PostTask(
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   message_loop_.Run();
 
   ASSERT_TRUE(shared_memory_ != NULL);
diff --git a/chrome/browser/extensions/permissions_updater_unittest.cc b/chrome/browser/extensions/permissions_updater_unittest.cc
index 91e383e..2f4470f 100644
--- a/chrome/browser/extensions/permissions_updater_unittest.cc
+++ b/chrome/browser/extensions/permissions_updater_unittest.cc
@@ -161,7 +161,7 @@ class PermissionsUpdaterListener : public content::NotificationObserver {
 
     if (waiting_) {
       waiting_ = false;
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/external_protocol/external_protocol_handler_unittest.cc b/chrome/browser/external_protocol/external_protocol_handler_unittest.cc
index f7d3511..b247a6d 100644
--- a/chrome/browser/external_protocol/external_protocol_handler_unittest.cc
+++ b/chrome/browser/external_protocol/external_protocol_handler_unittest.cc
@@ -85,7 +85,7 @@ class FakeExternalProtocolHandlerDelegate
   }
 
   void FinishedProcessingCheck() override {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void set_os_state(ShellIntegration::DefaultWebClientState value) {
diff --git a/chrome/browser/first_run/try_chrome_dialog_view.cc b/chrome/browser/first_run/try_chrome_dialog_view.cc
index 47666e6..5918776 100644
--- a/chrome/browser/first_run/try_chrome_dialog_view.cc
+++ b/chrome/browser/first_run/try_chrome_dialog_view.cc
@@ -359,7 +359,7 @@ void TryChromeDialogView::ButtonPressed(views::Button* sender,
   }
 
   popup_->Close();
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void TryChromeDialogView::LinkClicked(views::Link* source, int event_flags) {
diff --git a/chrome/browser/geolocation/access_token_store_browsertest.cc b/chrome/browser/geolocation/access_token_store_browsertest.cc
index 36acb04..803756e 100644
--- a/chrome/browser/geolocation/access_token_store_browsertest.cc
+++ b/chrome/browser/geolocation/access_token_store_browsertest.cc
@@ -99,8 +99,8 @@ void GeolocationAccessTokenStoreTest::OnAccessTokenStoresLoaded(
     scoped_refptr<AccessTokenStore> store(new ChromeAccessTokenStore());
     store->SaveAccessToken(ref_url_, *token_to_set_);
   }
-  BrowserThread::PostTask(
-      BrowserThread::UI, FROM_HERE, base::MessageLoop::QuitClosure());
+  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
+                          base::MessageLoop::QuitWhenIdleClosure());
 }
 
 IN_PROC_BROWSER_TEST_F(GeolocationAccessTokenStoreTest, SetAcrossInstances) {
diff --git a/chrome/browser/geolocation/geolocation_browsertest.cc b/chrome/browser/geolocation/geolocation_browsertest.cc
index fc44f49..c8ff648 100644
--- a/chrome/browser/geolocation/geolocation_browsertest.cc
+++ b/chrome/browser/geolocation/geolocation_browsertest.cc
@@ -122,7 +122,7 @@ void IFrameLoader::Observe(int type,
     javascript_completed_ = true;
   }
   if (javascript_completed_ && navigation_completed_)
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
 }
 
 // PermissionBubbleObserver ---------------------------------------------------
diff --git a/chrome/browser/history/android/android_history_provider_service_unittest.cc b/chrome/browser/history/android/android_history_provider_service_unittest.cc
index 0166f3c..4124971 100644
--- a/chrome/browser/history/android/android_history_provider_service_unittest.cc
+++ b/chrome/browser/history/android/android_history_provider_service_unittest.cc
@@ -106,30 +106,30 @@ class CallbackHelper : public base::RefCountedThreadSafe<CallbackHelper> {
 
   void OnInserted(int64 id) {
     success_ = id != 0;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void OnQueryResult(AndroidStatement* statement) {
     success_ = statement != NULL;
     statement_ = statement;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void OnUpdated(int count) {
     success_ = count != 0;
     count_ = count;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void OnDeleted(int count) {
     success_ = count != 0;
     count_ = count;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void OnStatementMoved(int cursor_position) {
     cursor_position_ = cursor_position;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
  private:
diff --git a/chrome/browser/history/android/sqlite_cursor.h b/chrome/browser/history/android/sqlite_cursor.h
index 97f85bd..c828ad2 100644
--- a/chrome/browser/history/android/sqlite_cursor.h
+++ b/chrome/browser/history/android/sqlite_cursor.h
@@ -45,8 +45,8 @@ class SQLiteCursor {
   // give unit tests a chance to run the message loop before event_.Wait is
   // invoked, The OnGetMoveToResult() and OnGetFaviconResult() is used to notify
   // the test observer in the UI thread when the task's result comes back, it
-  // calls MessageLoop::Quit() to exit the loop, then the event.Wait() is
-  // called. Basically, Two threads are used to simulate 3 threads' behavior
+  // calls MessageLoop::QuitWhenIdle() to exit the loop, then the event.Wait()
+  // is called. Basically, Two threads are used to simulate 3 threads' behavior
   // here.
   // The whole observer design is only for test purpose and should only be used
   // in unit test.
diff --git a/chrome/browser/history/android/sqlite_cursor_unittest.cc b/chrome/browser/history/android/sqlite_cursor_unittest.cc
index 858f5e4..63b4d8ad 100644
--- a/chrome/browser/history/android/sqlite_cursor_unittest.cc
+++ b/chrome/browser/history/android/sqlite_cursor_unittest.cc
@@ -80,11 +80,15 @@ class SQLiteCursorTest : public testing::Test,
   // Override SQLiteCursor::TestObserver.
   void OnPostMoveToTask() override { base::MessageLoop::current()->Run(); }
 
-  void OnGetMoveToResult() override { base::MessageLoop::current()->Quit(); }
+  void OnGetMoveToResult() override {
+    base::MessageLoop::current()->QuitWhenIdle();
+  }
 
   void OnPostGetFaviconTask() override { base::MessageLoop::current()->Run(); }
 
-  void OnGetFaviconResult() override { base::MessageLoop::current()->Quit(); }
+  void OnGetFaviconResult() override {
+    base::MessageLoop::current()->QuitWhenIdle();
+  }
 
  protected:
   TestingProfileManager profile_manager_;
@@ -117,13 +121,13 @@ class CallbackHelper : public base::RefCountedThreadSafe<CallbackHelper> {
 
   void OnInserted(int64 id) {
     success_ = id != 0;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void OnQueryResult(AndroidStatement* statement) {
     success_ = statement != NULL;
     statement_ = statement;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
  private:
diff --git a/chrome/browser/history/history_browsertest.cc b/chrome/browser/history/history_browsertest.cc
index 0baf596..ae6f988 100644
--- a/chrome/browser/history/history_browsertest.cc
+++ b/chrome/browser/history/history_browsertest.cc
@@ -53,7 +53,9 @@ class WaitForHistoryTask : public history::HistoryDBTask {
     return true;
   }
 
-  void DoneRunOnMainThread() override { base::MessageLoop::current()->Quit(); }
+  void DoneRunOnMainThread() override {
+    base::MessageLoop::current()->QuitWhenIdle();
+  }
 
  private:
   ~WaitForHistoryTask() override {}
diff --git a/chrome/browser/history/redirect_browsertest.cc b/chrome/browser/history/redirect_browsertest.cc
index 2746370..f51c18f 100644
--- a/chrome/browser/history/redirect_browsertest.cc
+++ b/chrome/browser/history/redirect_browsertest.cc
@@ -64,7 +64,7 @@ class RedirectTest : public InProcessBrowserTest {
                                const history::RedirectList* redirects) {
     rv->insert(rv->end(), redirects->begin(), redirects->end());
     base::ThreadTaskRunnerHandle::Get()->PostTask(
-        FROM_HERE, base::MessageLoop::QuitClosure());
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   }
 
   // Tracker for asynchronous history queries.
diff --git a/chrome/browser/importer/firefox_importer_browsertest.cc b/chrome/browser/importer/firefox_importer_browsertest.cc
index 5f7d182..05ca389 100644
--- a/chrome/browser/importer/firefox_importer_browsertest.cc
+++ b/chrome/browser/importer/firefox_importer_browsertest.cc
@@ -144,7 +144,7 @@ class FirefoxObserver : public ProfileWriter,
   void ImportItemStarted(importer::ImportItem item) override {}
   void ImportItemEnded(importer::ImportItem item) override {}
   void ImportEnded() override {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
     EXPECT_EQ(arraysize(kFirefoxBookmarks), bookmark_count_);
     EXPECT_EQ(1U, history_count_);
     EXPECT_EQ(arraysize(kFirefoxPasswords), password_count_);
diff --git a/chrome/browser/importer/ie_importer_browsertest_win.cc b/chrome/browser/importer/ie_importer_browsertest_win.cc
index c1a8eb44..168ab45 100644
--- a/chrome/browser/importer/ie_importer_browsertest_win.cc
+++ b/chrome/browser/importer/ie_importer_browsertest_win.cc
@@ -240,7 +240,7 @@ class TestObserver : public ProfileWriter,
   void ImportItemStarted(importer::ImportItem item) override {}
   void ImportItemEnded(importer::ImportItem item) override {}
   void ImportEnded() override {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
     if (importer_items_ & importer::FAVORITES) {
       EXPECT_EQ(arraysize(kIEBookmarks), bookmark_count_);
       EXPECT_EQ(arraysize(kIEFaviconGroup), favicon_count_);
@@ -388,7 +388,7 @@ class MalformedFavoritesRegistryTestObserver
   void ImportItemStarted(importer::ImportItem item) override {}
   void ImportItemEnded(importer::ImportItem item) override {}
   void ImportEnded() override {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
     EXPECT_EQ(arraysize(kIESortedBookmarks), bookmark_count_);
   }
 
diff --git a/chrome/browser/importer/profile_writer_unittest.cc b/chrome/browser/importer/profile_writer_unittest.cc
index 74dd262..d49133e 100644
--- a/chrome/browser/importer/profile_writer_unittest.cc
+++ b/chrome/browser/importer/profile_writer_unittest.cc
@@ -102,7 +102,7 @@ class ProfileWriterTest : public testing::Test {
   }
 
   void HistoryQueryComplete(history::QueryResults* results) {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
     history_count_ = results->size();
   }
 
diff --git a/chrome/browser/local_discovery/privet_http_unittest.cc b/chrome/browser/local_discovery/privet_http_unittest.cc
index 1fbd4e3..1fd60be 100644
--- a/chrome/browser/local_discovery/privet_http_unittest.cc
+++ b/chrome/browser/local_discovery/privet_http_unittest.cc
@@ -337,9 +337,7 @@ class PrivetHTTPTest : public ::testing::Test {
     callback.Cancel();
   }
 
-  void Stop() {
-    base::MessageLoop::current()->Quit();
-  }
+  void Stop() { base::MessageLoop::current()->QuitWhenIdle(); }
 
  protected:
   base::MessageLoop loop_;
diff --git a/chrome/browser/local_discovery/privet_url_fetcher_unittest.cc b/chrome/browser/local_discovery/privet_url_fetcher_unittest.cc
index c2940aa6..be975f9 100644
--- a/chrome/browser/local_discovery/privet_url_fetcher_unittest.cc
+++ b/chrome/browser/local_discovery/privet_url_fetcher_unittest.cc
@@ -115,9 +115,7 @@ class PrivetURLFetcherTest : public ::testing::Test {
     callback.Cancel();
   }
 
-  void Stop() {
-    base::MessageLoop::current()->Quit();
-  }
+  void Stop() { base::MessageLoop::current()->QuitWhenIdle(); }
 
  protected:
   base::MessageLoop loop_;
diff --git a/chrome/browser/media/desktop_media_list_ash_unittest.cc b/chrome/browser/media/desktop_media_list_ash_unittest.cc
index d291dd2..49670b6 100644
--- a/chrome/browser/media/desktop_media_list_ash_unittest.cc
+++ b/chrome/browser/media/desktop_media_list_ash_unittest.cc
@@ -49,7 +49,7 @@ class DesktopMediaListAshTest : public ash::test::AshTestBase {
 
 ACTION(QuitMessageLoop) {
   base::ThreadTaskRunnerHandle::Get()->PostTask(
-      FROM_HERE, base::MessageLoop::QuitClosure());
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
 }
 
 TEST_F(DesktopMediaListAshTest, Screen) {
diff --git a/chrome/browser/media/native_desktop_media_list_unittest.cc b/chrome/browser/media/native_desktop_media_list_unittest.cc
index 7ae36ea..a5925e9 100644
--- a/chrome/browser/media/native_desktop_media_list_unittest.cc
+++ b/chrome/browser/media/native_desktop_media_list_unittest.cc
@@ -133,8 +133,8 @@ ACTION_P2(CheckListSize, model, expected_list_size) {
 }
 
 ACTION_P(QuitMessageLoop, message_loop) {
-  message_loop->task_runner()->PostTask(FROM_HERE,
-                                        base::MessageLoop::QuitClosure());
+  message_loop->task_runner()->PostTask(
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
 }
 
 class DesktopMediaListTest : public testing::Test {
diff --git a/chrome/browser/metrics/metrics_memory_details_browsertest.cc b/chrome/browser/metrics/metrics_memory_details_browsertest.cc
index d38bfda..4abccd8 100644
--- a/chrome/browser/metrics/metrics_memory_details_browsertest.cc
+++ b/chrome/browser/metrics/metrics_memory_details_browsertest.cc
@@ -28,7 +28,7 @@ class TestMemoryDetails : public MetricsMemoryDetails {
   void OnDetailsAvailable() override {
     MetricsMemoryDetails::OnDetailsAvailable();
     // Exit the loop initiated by StartFetchAndWait().
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   DISALLOW_COPY_AND_ASSIGN(TestMemoryDetails);
diff --git a/chrome/browser/metrics/thread_watcher_unittest.cc b/chrome/browser/metrics/thread_watcher_unittest.cc
index 43c6b5c..ea47fa3 100644
--- a/chrome/browser/metrics/thread_watcher_unittest.cc
+++ b/chrome/browser/metrics/thread_watcher_unittest.cc
@@ -701,7 +701,7 @@ TEST_F(ThreadWatcherListTest, Restart) {
   ThreadWatcherList::StartWatchingAll(*base::CommandLine::ForCurrentProcess());
   ThreadWatcherList::StopWatchingAll();
   message_loop_for_ui.task_runner()->PostDelayedTask(
-      FROM_HERE, message_loop_for_ui.QuitClosure(),
+      FROM_HERE, message_loop_for_ui.QuitWhenIdleClosure(),
       base::TimeDelta::FromSeconds(
           ThreadWatcherList::g_initialize_delay_seconds));
   message_loop_for_ui.Run();
@@ -713,7 +713,7 @@ TEST_F(ThreadWatcherListTest, Restart) {
   // Proceed with just |StartWatchingAll| and ensure it'll be started.
   ThreadWatcherList::StartWatchingAll(*base::CommandLine::ForCurrentProcess());
   message_loop_for_ui.task_runner()->PostDelayedTask(
-      FROM_HERE, message_loop_for_ui.QuitClosure(),
+      FROM_HERE, message_loop_for_ui.QuitWhenIdleClosure(),
       base::TimeDelta::FromSeconds(
           ThreadWatcherList::g_initialize_delay_seconds + 1));
   message_loop_for_ui.Run();
@@ -725,7 +725,7 @@ TEST_F(ThreadWatcherListTest, Restart) {
   // Finally, StopWatchingAll() must stop.
   ThreadWatcherList::StopWatchingAll();
   message_loop_for_ui.task_runner()->PostDelayedTask(
-      FROM_HERE, message_loop_for_ui.QuitClosure(),
+      FROM_HERE, message_loop_for_ui.QuitWhenIdleClosure(),
       base::TimeDelta::FromSeconds(
           ThreadWatcherList::g_initialize_delay_seconds));
   message_loop_for_ui.Run();
diff --git a/chrome/browser/net/dns_probe_browsertest.cc b/chrome/browser/net/dns_probe_browsertest.cc
index de664cf..1cb43e7 100644
--- a/chrome/browser/net/dns_probe_browsertest.cc
+++ b/chrome/browser/net/dns_probe_browsertest.cc
@@ -666,7 +666,7 @@ void DnsProbeBrowserTest::OnDnsProbeStatusSent(
     DnsProbeStatus dns_probe_status) {
   dns_probe_status_queue_.push_back(dns_probe_status);
   if (awaiting_dns_probe_status_)
-    MessageLoop::current()->Quit();
+    MessageLoop::current()->QuitWhenIdle();
 }
 
 // Make sure probes don't break non-DNS error pages when corrections load.
diff --git a/chrome/browser/net/predictor_browsertest.cc b/chrome/browser/net/predictor_browsertest.cc
index 502b39e..7260873 100644
--- a/chrome/browser/net/predictor_browsertest.cc
+++ b/chrome/browser/net/predictor_browsertest.cc
@@ -181,7 +181,7 @@ class HostResolutionRequestRecorder : public net::HostResolverProc {
     if (is_waiting_for_hostname_ && waiting_for_hostname_ == hostname) {
       is_waiting_for_hostname_ = false;
       waiting_for_hostname_.clear();
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/net/predictor_unittest.cc b/chrome/browser/net/predictor_unittest.cc
index 132f95c..00ed17f6 100644
--- a/chrome/browser/net/predictor_unittest.cc
+++ b/chrome/browser/net/predictor_unittest.cc
@@ -61,7 +61,7 @@ class WaitForResolutionHelper {
     // When all hostnames have been resolved, or we've hit the limit,
     // exit the loop.
     timer_->Stop();
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
     delete timer_;
     delete this;
   }
@@ -151,7 +151,7 @@ TEST_F(PredictorTest, ShutdownWhenResolutionIsPendingTest) {
   testing_master.ResolveList(names, UrlInfo::PAGE_SCAN_MOTIVATED);
 
   base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
-      FROM_HERE, base::MessageLoop::QuitClosure(),
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
       base::TimeDelta::FromMilliseconds(500));
   base::MessageLoop::current()->Run();
 
diff --git a/chrome/browser/net/sdch_browsertest.cc b/chrome/browser/net/sdch_browsertest.cc
index 406aeca..00c9a80 100644
--- a/chrome/browser/net/sdch_browsertest.cc
+++ b/chrome/browser/net/sdch_browsertest.cc
@@ -640,7 +640,7 @@ class SdchBrowserTest : public InProcessBrowserTest,
   void OnURLFetchComplete(const net::URLFetcher* source) override {
     url_fetch_complete_ = true;
     if (waiting_)
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   SdchResponseHandler response_handler_;
diff --git a/chrome/browser/password_manager/native_backend_gnome_x_unittest.cc b/chrome/browser/password_manager/native_backend_gnome_x_unittest.cc
index adcd284..c387919 100644
--- a/chrome/browser/password_manager/native_backend_gnome_x_unittest.cc
+++ b/chrome/browser/password_manager/native_backend_gnome_x_unittest.cc
@@ -405,7 +405,7 @@ class NativeBackendGnomeTest : public testing::Test {
 
   void TearDown() override {
     base::ThreadTaskRunnerHandle::Get()->PostTask(
-        FROM_HERE, base::MessageLoop::QuitClosure());
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
     base::MessageLoop::current()->Run();
     db_thread_.Stop();
   }
@@ -422,7 +422,8 @@ class NativeBackendGnomeTest : public testing::Test {
   }
 
   static void PostQuitTask(base::MessageLoop* loop) {
-    loop->task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+    loop->task_runner()->PostTask(FROM_HERE,
+                                  base::MessageLoop::QuitWhenIdleClosure());
   }
 
   void CheckUint32Attribute(const MockKeyringItem* item,
diff --git a/chrome/browser/password_manager/native_backend_kwallet_x_unittest.cc b/chrome/browser/password_manager/native_backend_kwallet_x_unittest.cc
index 7186cde..9f23b0d 100644
--- a/chrome/browser/password_manager/native_backend_kwallet_x_unittest.cc
+++ b/chrome/browser/password_manager/native_backend_kwallet_x_unittest.cc
@@ -388,7 +388,7 @@ void NativeBackendKWalletTest::SetUp() {
 
 void NativeBackendKWalletTest::TearDown() {
   base::ThreadTaskRunnerHandle::Get()->PostTask(
-      FROM_HERE, base::MessageLoop::QuitClosure());
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   base::MessageLoop::current()->Run();
   db_thread_.Stop();
 }
diff --git a/chrome/browser/password_manager/native_backend_libsecret_unittest.cc b/chrome/browser/password_manager/native_backend_libsecret_unittest.cc
index 759ba3f..c68673e 100644
--- a/chrome/browser/password_manager/native_backend_libsecret_unittest.cc
+++ b/chrome/browser/password_manager/native_backend_libsecret_unittest.cc
@@ -330,7 +330,7 @@ class NativeBackendLibsecretTest : public testing::Test {
 
   void TearDown() override {
     base::ThreadTaskRunnerHandle::Get()->PostTask(
-        FROM_HERE, base::MessageLoop::QuitClosure());
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
     base::MessageLoop::current()->Run();
     ASSERT_TRUE(global_mock_libsecret_items);
     global_mock_libsecret_items = nullptr;
diff --git a/chrome/browser/password_manager/password_store_mac_unittest.cc b/chrome/browser/password_manager/password_store_mac_unittest.cc
index 412e677..36cc507 100644
--- a/chrome/browser/password_manager/password_store_mac_unittest.cc
+++ b/chrome/browser/password_manager/password_store_mac_unittest.cc
@@ -50,7 +50,7 @@ namespace {
 
 ACTION(QuitUIMessageLoop) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 // From the mock's argument #0 of type const std::vector<PasswordForm*>& takes
diff --git a/chrome/browser/password_manager/password_store_proxy_mac_unittest.cc b/chrome/browser/password_manager/password_store_proxy_mac_unittest.cc
index d1bc400..a06e836 100644
--- a/chrome/browser/password_manager/password_store_proxy_mac_unittest.cc
+++ b/chrome/browser/password_manager/password_store_proxy_mac_unittest.cc
@@ -37,7 +37,7 @@ using testing::Pointee;
 
 ACTION(QuitUIMessageLoop) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 // Returns a change list corresponding to |form| being added.
diff --git a/chrome/browser/password_manager/password_store_win_unittest.cc b/chrome/browser/password_manager/password_store_win_unittest.cc
index c1c7ecb..173fe16 100644
--- a/chrome/browser/password_manager/password_store_win_unittest.cc
+++ b/chrome/browser/password_manager/password_store_win_unittest.cc
@@ -146,8 +146,8 @@ class PasswordStoreWinTest : public testing::Test {
     BrowserThread::PostTask(BrowserThread::DB, FROM_HERE,
         base::Bind(&base::WaitableEvent::Signal, base::Unretained(&done)));
     done.Wait();
-    base::MessageLoop::current()->PostTask(FROM_HERE,
-                                           base::MessageLoop::QuitClosure());
+    base::MessageLoop::current()->PostTask(
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
     base::MessageLoop::current()->Run();
     db_thread_.Stop();
   }
@@ -182,7 +182,7 @@ ACTION(STLDeleteElements0) {
 
 ACTION(QuitUIMessageLoop) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 MATCHER(EmptyWDResult, "") {
diff --git a/chrome/browser/policy/cloud/device_management_service_browsertest.cc b/chrome/browser/policy/cloud/device_management_service_browsertest.cc
index 76d13ed..cfe06fd 100644
--- a/chrome/browser/policy/cloud/device_management_service_browsertest.cc
+++ b/chrome/browser/policy/cloud/device_management_service_browsertest.cc
@@ -125,11 +125,10 @@ class DeviceManagementServiceIntegrationTest
   void PerformRegistration() {
     ExpectRequest();
     EXPECT_CALL(*this, OnJobDone(DM_STATUS_SUCCESS, _, _))
-        .WillOnce(
-            DoAll(Invoke(this,
-                         &DeviceManagementServiceIntegrationTest::RecordToken),
-                  InvokeWithoutArgs(base::MessageLoop::current(),
-                                    &base::MessageLoop::Quit)));
+        .WillOnce(DoAll(
+            Invoke(this, &DeviceManagementServiceIntegrationTest::RecordToken),
+            InvokeWithoutArgs(base::MessageLoop::current(),
+                              &base::MessageLoop::QuitWhenIdle)));
     scoped_ptr<DeviceManagementRequestJob> job(
         service_->CreateJob(DeviceManagementRequestJob::TYPE_REGISTRATION,
                             g_browser_process->system_request_context()));
@@ -186,11 +185,10 @@ IN_PROC_BROWSER_TEST_P(DeviceManagementServiceIntegrationTest,
 
   ExpectRequest();
   EXPECT_CALL(*this, OnJobDone(DM_STATUS_SUCCESS, _, _))
-      .WillOnce(
-          DoAll(Invoke(this,
-                       &DeviceManagementServiceIntegrationTest::RecordAuthCode),
-                InvokeWithoutArgs(base::MessageLoop::current(),
-                                  &base::MessageLoop::Quit)));
+      .WillOnce(DoAll(
+          Invoke(this, &DeviceManagementServiceIntegrationTest::RecordAuthCode),
+          InvokeWithoutArgs(base::MessageLoop::current(),
+                            &base::MessageLoop::QuitWhenIdle)));
   scoped_ptr<DeviceManagementRequestJob> job(service_->CreateJob(
       DeviceManagementRequestJob::TYPE_API_AUTH_CODE_FETCH,
       g_browser_process->system_request_context()));
@@ -212,7 +210,7 @@ IN_PROC_BROWSER_TEST_P(DeviceManagementServiceIntegrationTest, PolicyFetch) {
   ExpectRequest();
   EXPECT_CALL(*this, OnJobDone(DM_STATUS_SUCCESS, _, _))
       .WillOnce(InvokeWithoutArgs(base::MessageLoop::current(),
-                                  &base::MessageLoop::Quit));
+                                  &base::MessageLoop::QuitWhenIdle));
   scoped_ptr<DeviceManagementRequestJob> job(
       service_->CreateJob(DeviceManagementRequestJob::TYPE_POLICY_FETCH,
                           g_browser_process->system_request_context()));
@@ -232,7 +230,7 @@ IN_PROC_BROWSER_TEST_P(DeviceManagementServiceIntegrationTest, Unregistration) {
   ExpectRequest();
   EXPECT_CALL(*this, OnJobDone(DM_STATUS_SUCCESS, _, _))
       .WillOnce(InvokeWithoutArgs(base::MessageLoop::current(),
-                                  &base::MessageLoop::Quit));
+                                  &base::MessageLoop::QuitWhenIdle));
   scoped_ptr<DeviceManagementRequestJob> job(
       service_->CreateJob(DeviceManagementRequestJob::TYPE_UNREGISTRATION,
                           g_browser_process->system_request_context()));
@@ -248,7 +246,7 @@ IN_PROC_BROWSER_TEST_P(DeviceManagementServiceIntegrationTest, AutoEnrollment) {
   ExpectRequest();
   EXPECT_CALL(*this, OnJobDone(DM_STATUS_SUCCESS, _, _))
       .WillOnce(InvokeWithoutArgs(base::MessageLoop::current(),
-                                  &base::MessageLoop::Quit));
+                                  &base::MessageLoop::QuitWhenIdle));
   scoped_ptr<DeviceManagementRequestJob> job(
       service_->CreateJob(DeviceManagementRequestJob::TYPE_AUTO_ENROLLMENT,
                           g_browser_process->system_request_context()));
diff --git a/chrome/browser/policy/policy_browsertest.cc b/chrome/browser/policy/policy_browsertest.cc
index d965602..d4b38f3 100644
--- a/chrome/browser/policy/policy_browsertest.cc
+++ b/chrome/browser/policy/policy_browsertest.cc
@@ -295,17 +295,15 @@ class MakeRequestFail {
  public:
   // Sets up the filter on IO thread such that requests to |host| fail.
   explicit MakeRequestFail(const std::string& host) : host_(host) {
-    BrowserThread::PostTaskAndReply(
-        BrowserThread::IO, FROM_HERE,
-        base::Bind(MakeRequestFailOnIO, host_),
-        base::MessageLoop::QuitClosure());
+    BrowserThread::PostTaskAndReply(BrowserThread::IO, FROM_HERE,
+                                    base::Bind(MakeRequestFailOnIO, host_),
+                                    base::MessageLoop::QuitWhenIdleClosure());
     content::RunMessageLoop();
   }
   ~MakeRequestFail() {
-    BrowserThread::PostTaskAndReply(
-        BrowserThread::IO, FROM_HERE,
-        base::Bind(UndoMakeRequestFailOnIO, host_),
-        base::MessageLoop::QuitClosure());
+    BrowserThread::PostTaskAndReply(BrowserThread::IO, FROM_HERE,
+                                    base::Bind(UndoMakeRequestFailOnIO, host_),
+                                    base::MessageLoop::QuitWhenIdleClosure());
     content::RunMessageLoop();
   }
 
@@ -688,10 +686,9 @@ class PolicyTest : public InProcessBrowserTest {
     void OnScreenshotCompleted(
         ScreenshotGrabberObserver::Result screenshot_result,
         const base::FilePath& screenshot_path) override {
-      BrowserThread::PostTaskAndReply(BrowserThread::IO,
-                                      FROM_HERE,
+      BrowserThread::PostTaskAndReply(BrowserThread::IO, FROM_HERE,
                                       base::Bind(base::DoNothing),
-                                      base::MessageLoop::QuitClosure());
+                                      base::MessageLoop::QuitWhenIdleClosure());
     }
 
     ~QuitMessageLoopAfterScreenshot() override {}
diff --git a/chrome/browser/printing/cloud_print/test/cloud_print_proxy_process_browsertest.cc b/chrome/browser/printing/cloud_print/test/cloud_print_proxy_process_browsertest.cc
index 14a01fa..43ccc3f 100644
--- a/chrome/browser/printing/cloud_print/test/cloud_print_proxy_process_browsertest.cc
+++ b/chrome/browser/printing/cloud_print/test/cloud_print_proxy_process_browsertest.cc
@@ -364,7 +364,7 @@ class CloudPrintProxyPolicyStartupTest : public base::MultiProcessTest,
     void Notify() {
       seen_ = true;
       if (running_)
-        base::MessageLoopForUI::current()->Quit();
+        base::MessageLoopForUI::current()->QuitWhenIdle();
     }
 
    private:
diff --git a/chrome/browser/printing/print_job.cc b/chrome/browser/printing/print_job.cc
index 66473c27..6da0aa0 100644
--- a/chrome/browser/printing/print_job.cc
+++ b/chrome/browser/printing/print_job.cc
@@ -443,7 +443,7 @@ void PrintJob::HoldUntilStopIsCalled() {
 }
 
 void PrintJob::Quit() {
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 // Takes settings_ ownership and will be deleted in the receiving thread.
diff --git a/chrome/browser/printing/print_view_manager_base.cc b/chrome/browser/printing/print_view_manager_base.cc
index 84cabec..421bb1e 100644
--- a/chrome/browser/printing/print_view_manager_base.cc
+++ b/chrome/browser/printing/print_view_manager_base.cc
@@ -324,9 +324,9 @@ bool PrintViewManagerBase::RenderAllMissingPagesNow() {
   // to actually spool the pages, only to have the renderer generate them. Run
   // a message loop until we get our signal that the print job is satisfied.
   // PrintJob will send a ALL_PAGES_REQUESTED after having received all the
-  // pages it needs. MessageLoop::current()->Quit() will be called as soon as
-  // print_job_->document()->IsComplete() is true on either ALL_PAGES_REQUESTED
-  // or in DidPrintPage(). The check is done in
+  // pages it needs. MessageLoop::current()->QuitWhenIdle() will be called as
+  // soon as print_job_->document()->IsComplete() is true on either
+  // ALL_PAGES_REQUESTED or in DidPrintPage(). The check is done in
   // ShouldQuitFromInnerMessageLoop().
   // BLOCKS until all the pages are received. (Need to enable recursive task)
   if (!RunInnerMessageLoop()) {
@@ -345,7 +345,7 @@ void PrintViewManagerBase::ShouldQuitFromInnerMessageLoop() {
       inside_inner_message_loop_) {
     // We are in a message loop created by RenderAllMissingPagesNow. Quit from
     // it.
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
     inside_inner_message_loop_ = false;
   }
 }
@@ -451,9 +451,9 @@ bool PrintViewManagerBase::RunInnerMessageLoop() {
   // memory-bound.
   static const int kPrinterSettingsTimeout = 60000;
   base::OneShotTimer quit_timer;
-  quit_timer.Start(FROM_HERE,
-                   TimeDelta::FromMilliseconds(kPrinterSettingsTimeout),
-                   base::MessageLoop::current(), &base::MessageLoop::Quit);
+  quit_timer.Start(
+      FROM_HERE, TimeDelta::FromMilliseconds(kPrinterSettingsTimeout),
+      base::MessageLoop::current(), &base::MessageLoop::QuitWhenIdle);
 
   inside_inner_message_loop_ = true;
 
diff --git a/chrome/browser/printing/printing_layout_browsertest.cc b/chrome/browser/printing/printing_layout_browsertest.cc
index 4755a18..3ab5dff 100644
--- a/chrome/browser/printing/printing_layout_browsertest.cc
+++ b/chrome/browser/printing/printing_layout_browsertest.cc
@@ -80,7 +80,7 @@ class PrintingLayoutTest : public PrintingTest<InProcessBrowserTest>,
       case printing::JobEventDetails::JOB_DONE: {
         // Succeeded.
         base::MessageLoop::current()->PostTask(
-            FROM_HERE, base::MessageLoop::QuitClosure());
+            FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
         break;
       }
       case printing::JobEventDetails::USER_INIT_CANCELED:
@@ -88,7 +88,7 @@ class PrintingLayoutTest : public PrintingTest<InProcessBrowserTest>,
         // Failed.
         ASSERT_TRUE(false);
         base::MessageLoop::current()->PostTask(
-            FROM_HERE, base::MessageLoop::QuitClosure());
+            FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
         break;
       }
       case printing::JobEventDetails::NEW_DOC:
diff --git a/chrome/browser/profiles/profile_list_desktop_browsertest.cc b/chrome/browser/profiles/profile_list_desktop_browsertest.cc
index b49e226..bc0f641 100644
--- a/chrome/browser/profiles/profile_list_desktop_browsertest.cc
+++ b/chrome/browser/profiles/profile_list_desktop_browsertest.cc
@@ -24,7 +24,7 @@ namespace {
 void OnUnblockOnProfileCreation(Profile* profile,
                                 Profile::CreateStatus status) {
   if (status == Profile::CREATE_STATUS_INITIALIZED)
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
 }
 
 }  // namespace
diff --git a/chrome/browser/profiles/profile_manager_browsertest.cc b/chrome/browser/profiles/profile_manager_browsertest.cc
index 51af357..b9c7222 100644
--- a/chrome/browser/profiles/profile_manager_browsertest.cc
+++ b/chrome/browser/profiles/profile_manager_browsertest.cc
@@ -54,7 +54,7 @@ void ProfileCreationComplete(Profile* profile, Profile::CreateStatus status) {
   EXPECT_EQ(chrome::GetTotalBrowserCountForProfile(profile), 0U);
   EXPECT_EQ(chrome::GetTotalBrowserCount(), 1U);
   if (status == Profile::CREATE_STATUS_INITIALIZED)
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void EphemeralProfileCreationComplete(Profile* profile,
diff --git a/chrome/browser/profiles/profile_shortcut_manager_unittest_win.cc b/chrome/browser/profiles/profile_shortcut_manager_unittest_win.cc
index 6a9bfd3..44b0f91 100644
--- a/chrome/browser/profiles/profile_shortcut_manager_unittest_win.cc
+++ b/chrome/browser/profiles/profile_shortcut_manager_unittest_win.cc
@@ -87,8 +87,8 @@ class ProfileShortcutManagerTest : public testing::Test {
   }
 
   void RunPendingTasks() {
-    base::MessageLoop::current()->PostTask(FROM_HERE,
-                                           base::MessageLoop::QuitClosure());
+    base::MessageLoop::current()->PostTask(
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
     base::MessageLoop::current()->Run();
   }
 
diff --git a/chrome/browser/profiles/profile_window_browsertest.cc b/chrome/browser/profiles/profile_window_browsertest.cc
index 16fc0fc..817b46b 100644
--- a/chrome/browser/profiles/profile_window_browsertest.cc
+++ b/chrome/browser/profiles/profile_window_browsertest.cc
@@ -54,7 +54,9 @@ class WaitForHistoryTask : public history::HistoryDBTask {
     return true;
   }
 
-  void DoneRunOnMainThread() override { base::MessageLoop::current()->Quit(); }
+  void DoneRunOnMainThread() override {
+    base::MessageLoop::current()->QuitWhenIdle();
+  }
 
  private:
   ~WaitForHistoryTask() override {}
diff --git a/chrome/browser/renderer_host/render_process_host_chrome_browsertest.cc b/chrome/browser/renderer_host/render_process_host_chrome_browsertest.cc
index fb7606c9..32a26fc 100644
--- a/chrome/browser/renderer_host/render_process_host_chrome_browsertest.cc
+++ b/chrome/browser/renderer_host/render_process_host_chrome_browsertest.cc
@@ -119,7 +119,7 @@ class ChromeRenderProcessHostTest : public InProcessBrowserTest {
   void WaitForLauncherThread() {
     content::BrowserThread::PostTaskAndReply(
         content::BrowserThread::PROCESS_LAUNCHER, FROM_HERE,
-        base::Bind(&base::DoNothing), base::MessageLoop::QuitClosure());
+        base::Bind(&base::DoNothing), base::MessageLoop::QuitWhenIdleClosure());
     base::MessageLoop::current()->Run();
   }
 
diff --git a/chrome/browser/safe_browsing/browser_feature_extractor_unittest.cc b/chrome/browser/safe_browsing/browser_feature_extractor_unittest.cc
index 32e3e69..612156f 100644
--- a/chrome/browser/safe_browsing/browser_feature_extractor_unittest.cc
+++ b/chrome/browser/safe_browsing/browser_feature_extractor_unittest.cc
@@ -220,7 +220,7 @@ class BrowserFeatureExtractorTest : public ChromeRenderViewHostTestHarness {
     // the test case which passed it to ExtractFeatures above.
     success_[request.release()] = success;
     if (--num_pending_ == 0) {
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
     }
   }
 
@@ -233,7 +233,7 @@ class BrowserFeatureExtractorTest : public ChromeRenderViewHostTestHarness {
     // the test case which passed it to ExtractMalwareFeatures above.
     success_[request.release()] = success;
     if (--num_pending_ == 0) {
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 };
diff --git a/chrome/browser/safe_browsing/client_side_detection_host_unittest.cc b/chrome/browser/safe_browsing/client_side_detection_host_unittest.cc
index bb744cc..20a6464 100644
--- a/chrome/browser/safe_browsing/client_side_detection_host_unittest.cc
+++ b/chrome/browser/safe_browsing/client_side_detection_host_unittest.cc
@@ -90,7 +90,7 @@ MATCHER(CallbackIsNull, "") {
 
 ACTION(QuitUIMessageLoop) {
   EXPECT_TRUE(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  base::MessageLoopForUI::current()->Quit();
+  base::MessageLoopForUI::current()->QuitWhenIdle();
 }
 
 ACTION_P(InvokeDoneCallback, verdict) {
diff --git a/chrome/browser/safe_browsing/client_side_detection_service_unittest.cc b/chrome/browser/safe_browsing/client_side_detection_service_unittest.cc
index ca40838..59411cc 100644
--- a/chrome/browser/safe_browsing/client_side_detection_service_unittest.cc
+++ b/chrome/browser/safe_browsing/client_side_detection_service_unittest.cc
@@ -236,7 +236,7 @@ class ClientSideDetectionServiceTest : public testing::Test {
   void SendRequestDone(GURL phishing_url, bool is_phishing) {
     ASSERT_EQ(phishing_url, phishing_url_);
     is_phishing_ = is_phishing;
-    msg_loop_.Quit();
+    msg_loop_.QuitWhenIdle();
   }
 
   void SendMalwareRequestDone(GURL original_url, GURL malware_url,
@@ -244,7 +244,7 @@ class ClientSideDetectionServiceTest : public testing::Test {
     ASSERT_EQ(phishing_url_, original_url);
     confirmed_malware_url_ = malware_url;
     is_malware_ = is_malware;
-    msg_loop_.Quit();
+    msg_loop_.QuitWhenIdle();
   }
 
   scoped_ptr<content::TestBrowserThread> browser_thread_;
diff --git a/chrome/browser/safe_browsing/download_protection_service_unittest.cc b/chrome/browser/safe_browsing/download_protection_service_unittest.cc
index cd27712..2606c2f 100644
--- a/chrome/browser/safe_browsing/download_protection_service_unittest.cc
+++ b/chrome/browser/safe_browsing/download_protection_service_unittest.cc
@@ -343,9 +343,7 @@ class DownloadProtectionServiceTest : public testing::Test {
                    base::Unretained(this)));
   }
 
-  void QuitMessageLoop() {
-    base::MessageLoop::current()->Quit();
-  }
+  void QuitMessageLoop() { base::MessageLoop::current()->QuitWhenIdle(); }
 
   void PostRunMessageLoopTask(BrowserThread::ID thread) {
     BrowserThread::PostTask(
@@ -377,7 +375,7 @@ class DownloadProtectionServiceTest : public testing::Test {
       DownloadProtectionService::DownloadCheckResult result) {
     result_ = result;
     has_result_ = true;
-    MessageLoop::current()->Quit();
+    MessageLoop::current()->QuitWhenIdle();
   }
 
   void SyncCheckDoneCallback(
diff --git a/chrome/browser/safe_browsing/safe_browsing_blocking_page_test.cc b/chrome/browser/safe_browsing/safe_browsing_blocking_page_test.cc
index 99488eac..96f8352 100644
--- a/chrome/browser/safe_browsing/safe_browsing_blocking_page_test.cc
+++ b/chrome/browser/safe_browsing/safe_browsing_blocking_page_test.cc
@@ -266,7 +266,7 @@ class FakeMalwareDetails : public MalwareDetails {
   void OnDOMDetailsDone() {
     got_dom_ = true;
     if (waiting_) {
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 
@@ -315,7 +315,7 @@ class TestSafeBrowsingBlockingPage : public SafeBrowsingBlockingPage {
       return;
 
     // Notify that we are gone
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
     wait_for_delete_ = false;
   }
 
diff --git a/chrome/browser/safe_browsing/safe_browsing_service_browsertest.cc b/chrome/browser/safe_browsing/safe_browsing_service_browsertest.cc
index e98c15d..5a98689 100644
--- a/chrome/browser/safe_browsing/safe_browsing_service_browsertest.cc
+++ b/chrome/browser/safe_browsing/safe_browsing_service_browsertest.cc
@@ -876,9 +876,7 @@ class TestSBClient
                             base::Bind(&TestSBClient::CheckDone, this));
   }
 
-  void CheckDone() {
-    base::MessageLoopForUI::current()->Quit();
-  }
+  void CheckDone() { base::MessageLoopForUI::current()->QuitWhenIdle(); }
 
   SBThreatType threat_type_;
   SafeBrowsingService* safe_browsing_service_;
@@ -1149,7 +1147,7 @@ class SafeBrowsingServiceShutdownTest : public SafeBrowsingServiceTest {
                                   Profile::CreateStatus status) {
     if (status == Profile::CREATE_STATUS_INITIALIZED) {
       profile2_ = profile;
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/safe_browsing/safe_browsing_test.cc b/chrome/browser/safe_browsing/safe_browsing_test.cc
index 9e0d347..60b215e 100644
--- a/chrome/browser/safe_browsing/safe_browsing_test.cc
+++ b/chrome/browser/safe_browsing/safe_browsing_test.cc
@@ -472,7 +472,7 @@ class SafeBrowsingServerTestHelper
   // Stops UI loop after desired status is updated.
   void StopUILoop() {
     EXPECT_TRUE(BrowserThread::CurrentlyOn(BrowserThread::UI));
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   // Fetch a URL. If message_loop_started is true, starts the message loop
diff --git a/chrome/browser/service_process/service_process_control_browsertest.cc b/chrome/browser/service_process/service_process_control_browsertest.cc
index 2be64a7..8228194 100644
--- a/chrome/browser/service_process/service_process_control_browsertest.cc
+++ b/chrome/browser/service_process/service_process_control_browsertest.cc
@@ -55,7 +55,7 @@ class ServiceProcessControlBrowserTest
   }
 
   static void QuitMessageLoop() {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   static void CloudPrintInfoCallback(
@@ -111,14 +111,14 @@ class ServiceProcessControlBrowserTest
     // because this can get invoked in the context of a Launch() call and we
     // may not be in Run() yet.
     base::ThreadTaskRunnerHandle::Get()->PostTask(
-        FROM_HERE, base::MessageLoop::QuitClosure());
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   }
 
   void ProcessControlLaunchFailed() {
     ADD_FAILURE();
     // Quit the current message.
     base::ThreadTaskRunnerHandle::Get()->PostTask(
-        FROM_HERE, base::MessageLoop::QuitClosure());
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   }
 
  private:
@@ -200,7 +200,7 @@ static void DecrementUntilZero(int* count) {
   (*count)--;
   if (!(*count))
     base::ThreadTaskRunnerHandle::Get()->PostTask(
-        FROM_HERE, base::MessageLoop::QuitClosure());
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
 }
 
 // Flaky on Mac. http://crbug.com/517420
@@ -218,7 +218,7 @@ IN_PROC_BROWSER_TEST_F(ServiceProcessControlBrowserTest,
   for (int i = 0; i < launch_count; i++) {
     // Launch the process asynchronously.
     process->Launch(base::Bind(&DecrementUntilZero, &launch_count),
-                    base::MessageLoop::QuitClosure());
+                    base::MessageLoop::QuitWhenIdleClosure());
   }
   // Then run the message loop to keep things running.
   content::RunMessageLoop();
diff --git a/chrome/browser/site_details_browsertest.cc b/chrome/browser/site_details_browsertest.cc
index 43c955a..bd3420fc 100644
--- a/chrome/browser/site_details_browsertest.cc
+++ b/chrome/browser/site_details_browsertest.cc
@@ -61,7 +61,7 @@ class TestMemoryDetails : public MetricsMemoryDetails {
   void OnDetailsAvailable() override {
     MetricsMemoryDetails::OnDetailsAvailable();
     // Exit the loop initiated by StartFetchAndWait().
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   scoped_ptr<base::HistogramTester> uma_;
diff --git a/chrome/browser/spellchecker/spellcheck_message_filter_platform_mac_browsertest.cc b/chrome/browser/spellchecker/spellcheck_message_filter_platform_mac_browsertest.cc
index 591513c..4e15232 100644
--- a/chrome/browser/spellchecker/spellcheck_message_filter_platform_mac_browsertest.cc
+++ b/chrome/browser/spellchecker/spellcheck_message_filter_platform_mac_browsertest.cc
@@ -24,7 +24,7 @@ class TestingSpellCheckMessageFilter : public SpellCheckMessageFilterPlatform {
 
   bool Send(IPC::Message* message) override {
     sent_messages_.push_back(message);
-    loop_->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+    loop_->PostTask(FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
     return true;
   }
 
diff --git a/chrome/browser/spellchecker/spellcheck_platform_mac_unittest.cc b/chrome/browser/spellchecker/spellcheck_platform_mac_unittest.cc
index 4375e00..c8dbe9d 100644
--- a/chrome/browser/spellchecker/spellcheck_platform_mac_unittest.cc
+++ b/chrome/browser/spellchecker/spellcheck_platform_mac_unittest.cc
@@ -32,7 +32,7 @@ class SpellcheckPlatformMacTest: public testing::Test {
  private:
   void QuitMessageLoop() {
     CHECK(base::MessageLoop::current() == &message_loop_);
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void CompletionCallback(const std::vector<SpellCheckResult>& results) {
diff --git a/chrome/browser/ssl/ssl_browser_tests.cc b/chrome/browser/ssl/ssl_browser_tests.cc
index 8b79012..cd4a177 100644
--- a/chrome/browser/ssl/ssl_browser_tests.cc
+++ b/chrome/browser/ssl/ssl_browser_tests.cc
@@ -125,7 +125,7 @@ class ProvisionalLoadWaiter : public content::WebContentsObserver {
       bool was_ignored_by_handler) override {
     seen_ = true;
     if (waiting_)
-      base::MessageLoopForUI::current()->Quit();
+      base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
  private:
@@ -336,7 +336,7 @@ class SSLUITest
 
       // Wait a bit.
       base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
-          FROM_HERE, base::MessageLoop::QuitClosure(),
+          FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
           base::TimeDelta::FromMilliseconds(kTimeoutMS));
       content::RunMessageLoop();
     }
@@ -1760,7 +1760,7 @@ IN_PROC_BROWSER_TEST_F(SSLUITest, DISABLED_TestCloseTabWithUnsafePopup) {
     if (IsShowingWebContentsModalDialog())
       break;
     base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
-        FROM_HERE, base::MessageLoop::QuitClosure(),
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
         base::TimeDelta::FromSeconds(1));
     content::RunMessageLoop();
   }
diff --git a/chrome/browser/sync/glue/browser_thread_model_worker_unittest.cc b/chrome/browser/sync/glue/browser_thread_model_worker_unittest.cc
index 9d6891ca..aa78da1 100644
--- a/chrome/browser/sync/glue/browser_thread_model_worker_unittest.cc
+++ b/chrome/browser/sync/glue/browser_thread_model_worker_unittest.cc
@@ -60,8 +60,8 @@ class SyncBrowserThreadModelWorkerTest : public testing::Test {
   syncer::SyncerError DoWork() {
     EXPECT_TRUE(BrowserThread::CurrentlyOn(BrowserThread::DB));
     timer_.Stop();  // Stop the failure timer so the test succeeds.
-    BrowserThread::PostTask(
-        BrowserThread::IO, FROM_HERE, base::MessageLoop::QuitClosure());
+    BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
+                            base::MessageLoop::QuitWhenIdleClosure());
     did_do_work_ = true;
     return syncer::SYNCER_OK;
   }
@@ -70,8 +70,8 @@ class SyncBrowserThreadModelWorkerTest : public testing::Test {
   // DoWork is called first.
   void Timeout() {
     ADD_FAILURE() << "Timed out waiting for work to be done on the DB thread.";
-    BrowserThread::PostTask(
-        BrowserThread::IO, FROM_HERE, base::MessageLoop::QuitClosure());
+    BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
+                            base::MessageLoop::QuitWhenIdleClosure());
   }
 
  protected:
diff --git a/chrome/browser/sync/glue/sync_backend_host_impl_unittest.cc b/chrome/browser/sync/glue/sync_backend_host_impl_unittest.cc
index 4c09eea..d424388 100644
--- a/chrome/browser/sync/glue/sync_backend_host_impl_unittest.cc
+++ b/chrome/browser/sync/glue/sync_backend_host_impl_unittest.cc
@@ -70,7 +70,7 @@ ACTION_P(Signal, event) {
 }
 
 void QuitMessageLoop() {
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 class MockSyncFrontend : public sync_driver::SyncFrontend {
@@ -274,7 +274,7 @@ class SyncBackendHostTest : public testing::Test {
  protected:
   void DownloadReady(syncer::ModelTypeSet succeeded_types,
                      syncer::ModelTypeSet failed_types) {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void OnDownloadRetry() {
diff --git a/chrome/browser/sync/glue/ui_model_worker_unittest.cc b/chrome/browser/sync/glue/ui_model_worker_unittest.cc
index e0e02cc..f256eee 100644
--- a/chrome/browser/sync/glue/ui_model_worker_unittest.cc
+++ b/chrome/browser/sync/glue/ui_model_worker_unittest.cc
@@ -31,7 +31,7 @@ class UIModelWorkerVisitor {
     EXPECT_TRUE(BrowserThread::CurrentlyOn(BrowserThread::UI));
     was_run_->Signal();
     if (quit_loop_when_run_)
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
     return syncer::SYNCER_OK;
   }
 
diff --git a/chrome/browser/sync/profile_sync_test_util.h b/chrome/browser/sync/profile_sync_test_util.h
index 2fb4274..7062907 100644
--- a/chrome/browser/sync/profile_sync_test_util.h
+++ b/chrome/browser/sync/profile_sync_test_util.h
@@ -30,7 +30,7 @@ ACTION_P(Notify, type) {
 
 ACTION(QuitUIMessageLoop) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 class SyncServiceObserverMock : public sync_driver::SyncServiceObserver {
diff --git a/chrome/browser/sync/test/integration/bookmarks_helper.cc b/chrome/browser/sync/test/integration/bookmarks_helper.cc
index aa9aba7..4b5db5c 100644
--- a/chrome/browser/sync/test/integration/bookmarks_helper.cc
+++ b/chrome/browser/sync/test/integration/bookmarks_helper.cc
@@ -129,7 +129,7 @@ class FaviconChangeObserver : public bookmarks::BookmarkModelObserver {
                                   const BookmarkNode* node) override {
     if (model == model_ && node == node_) {
       if (!wait_for_load_ || (wait_for_load_ && node->is_favicon_loaded()))
-        base::MessageLoopForUI::current()->Quit();
+        base::MessageLoopForUI::current()->QuitWhenIdle();
     }
   }
 
diff --git a/chrome/browser/sync/test/integration/passwords_helper.cc b/chrome/browser/sync/test/integration/passwords_helper.cc
index ade29b6..4b9de83 100644
--- a/chrome/browser/sync/test/integration/passwords_helper.cc
+++ b/chrome/browser/sync/test/integration/passwords_helper.cc
@@ -48,7 +48,7 @@ class PasswordStoreConsumerHelper
   void OnGetPasswordStoreResults(ScopedVector<PasswordForm> results) override {
     result_.swap(results);
     // Quit the message loop to wake up passwords_helper::GetLogins.
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
   }
 
   ScopedVector<PasswordForm> result() { return result_.Pass(); }
diff --git a/chrome/browser/sync/test/integration/sessions_helper.cc b/chrome/browser/sync/test/integration/sessions_helper.cc
index d8ecce4..d69baa2 100644
--- a/chrome/browser/sync/test/integration/sessions_helper.cc
+++ b/chrome/browser/sync/test/integration/sessions_helper.cc
@@ -156,9 +156,7 @@ class TabEventHandler : public browser_sync::LocalSessionEventHandler {
   }
 
  private:
-  void QuitLoop() {
-    base::MessageLoop::current()->Quit();
-  }
+  void QuitLoop() { base::MessageLoop::current()->QuitWhenIdle(); }
 
   base::WeakPtrFactory<TabEventHandler> weak_factory_;
 };
diff --git a/chrome/browser/sync/test/integration/sync_test.cc b/chrome/browser/sync/test/integration/sync_test.cc
index 1e37357..53fd6b8 100644
--- a/chrome/browser/sync/test/integration/sync_test.cc
+++ b/chrome/browser/sync/test/integration/sync_test.cc
@@ -116,7 +116,7 @@ class SyncServerStatusChecker : public net::URLFetcherDelegate {
     running_ =
         (source->GetStatus().status() == net::URLRequestStatus::SUCCESS &&
         source->GetResponseCode() == 200 && data.find("ok") == 0);
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   bool running() const { return running_; }
diff --git a/chrome/browser/sync/test_profile_sync_service.cc b/chrome/browser/sync/test_profile_sync_service.cc
index 323b957..6ee7799 100644
--- a/chrome/browser/sync/test_profile_sync_service.cc
+++ b/chrome/browser/sync/test_profile_sync_service.cc
@@ -181,7 +181,7 @@ TestProfileSyncService::GetSyncApiComponentFactoryMock() {
 void TestProfileSyncService::OnConfigureDone(
     const sync_driver::DataTypeManager::ConfigureResult& result) {
   ProfileSyncService::OnConfigureDone(result);
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 UserShare* TestProfileSyncService::GetUserShare() const {
diff --git a/chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc b/chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc
index 46f4c6d..82b4989 100644
--- a/chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc
+++ b/chrome/browser/sync_file_system/local/local_file_sync_context_unittest.cc
@@ -132,7 +132,7 @@ class LocalFileSyncContextTest : public testing::Test {
     *changes_out = sync_file_info.changes;
     if (snapshot_out)
       *snapshot_out = snapshot.Pass();
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   SyncStatusCode ApplyRemoteChange(FileSystemContext* file_system_context,
@@ -169,7 +169,7 @@ class LocalFileSyncContextTest : public testing::Test {
     sync_context_->FinalizeExclusiveSync(
         file_system_context, url,
         status == SYNC_STATUS_OK /* clear_local_changes */,
-        base::MessageLoop::QuitClosure());
+        base::MessageLoop::QuitWhenIdleClosure());
   }
 
   void StartModifyFileOnIOThread(CannedSyncableFileSystem* file_system,
diff --git a/chrome/browser/sync_file_system/local/syncable_file_operation_runner_unittest.cc b/chrome/browser/sync_file_system/local/syncable_file_operation_runner_unittest.cc
index 9d477c9..2391dcc 100644
--- a/chrome/browser/sync_file_system/local/syncable_file_operation_runner_unittest.cc
+++ b/chrome/browser/sync_file_system/local/syncable_file_operation_runner_unittest.cc
@@ -132,7 +132,7 @@ class SyncableFileOperationRunnerTest : public testing::Test {
     SCOPED_TRACE(testing::Message() << location.ToString());
     EXPECT_EQ(expect, status);
     ++callback_count_;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   bool CreateTempFile(base::FilePath* path) {
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 e10c952..44eded2 100644
--- a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_unittest.cc
+++ b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_unittest.cc
@@ -800,8 +800,8 @@ class MultiProfileMultiBrowserShelfLayoutChromeLauncherControllerTest
 
     // A Task is leaked if we don't destroy everything, then run the message
     // loop.
-    base::MessageLoop::current()->PostTask(FROM_HERE,
-                                           base::MessageLoop::QuitClosure());
+    base::MessageLoop::current()->PostTask(
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
     base::MessageLoop::current()->Run();
   }
 
diff --git a/chrome/browser/ui/browser_browsertest.cc b/chrome/browser/ui/browser_browsertest.cc
index 89435cc..3b5e683 100644
--- a/chrome/browser/ui/browser_browsertest.cc
+++ b/chrome/browser/ui/browser_browsertest.cc
@@ -1043,7 +1043,7 @@ class BeforeUnloadAtQuitWithTwoWindows : public InProcessBrowserTest {
     // Run the application event loop to completion, which will cycle the
     // native MessagePump on all platforms.
     base::MessageLoop::current()->task_runner()->PostTask(
-        FROM_HERE, base::MessageLoop::QuitClosure());
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
     base::MessageLoop::current()->Run();
 
     // Take care of any remaining Cocoa work.
diff --git a/chrome/browser/ui/browser_focus_uitest.cc b/chrome/browser/ui/browser_focus_uitest.cc
index 7511437..1667d7a 100644
--- a/chrome/browser/ui/browser_focus_uitest.cc
+++ b/chrome/browser/ui/browser_focus_uitest.cc
@@ -202,7 +202,7 @@ IN_PROC_BROWSER_TEST_F(BrowserFocusTest, MAYBE_ClickingMovesFocus) {
   // It seems we have to wait a little bit for the widgets to spin up before
   // we can start clicking on them.
   base::MessageLoop::current()->task_runner()->PostDelayedTask(
-      FROM_HERE, base::MessageLoop::QuitClosure(),
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
       base::TimeDelta::FromMilliseconds(kActionDelayMs));
   content::RunMessageLoop();
 #endif  // defined(OS_POSIX)
diff --git a/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_folder_hover_state_unittest.mm b/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_folder_hover_state_unittest.mm
index f9a95ba..f31befc 100644
--- a/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_folder_hover_state_unittest.mm
+++ b/chrome/browser/ui/cocoa/bookmarks/bookmark_bar_folder_hover_state_unittest.mm
@@ -47,7 +47,7 @@ TEST_F(BookmarkBarFolderHoverStateTest, HoverState) {
   // Test transition from opening to opened.
   message_loop.PostDelayedTask(
       FROM_HERE,
-      base::MessageLoop::QuitClosure(),
+      base::MessageLoop::QuitWhenIdleClosure(),
       base::TimeDelta::FromMilliseconds(
           bookmarks::kDragHoverOpenDelay * 1000.0 * 1.5));
   message_loop.Run();
@@ -68,7 +68,7 @@ TEST_F(BookmarkBarFolderHoverStateTest, HoverState) {
   ASSERT_EQ(kHoverStateClosing, [bbfhs hoverState]);
   message_loop.PostDelayedTask(
       FROM_HERE,
-      base::MessageLoop::QuitClosure(),
+      base::MessageLoop::QuitWhenIdleClosure(),
       base::TimeDelta::FromMilliseconds(
           bookmarks::kDragHoverCloseDelay * 1000.0 * 1.5));
   message_loop.Run();
diff --git a/chrome/browser/ui/cocoa/location_bar/zoom_decoration_browsertest.mm b/chrome/browser/ui/cocoa/location_bar/zoom_decoration_browsertest.mm
index 61ef358..4261962 100644
--- a/chrome/browser/ui/cocoa/location_bar/zoom_decoration_browsertest.mm
+++ b/chrome/browser/ui/cocoa/location_bar/zoom_decoration_browsertest.mm
@@ -64,9 +64,10 @@ class ZoomDecorationTest : public InProcessBrowserTest {
 
   void OnZoomChanged(const content::HostZoomMap::ZoomLevelChange& host) {
     if (should_quit_on_zoom_) {
-      base::MessageLoop::current()->PostTask(FROM_HERE, base::Bind(
-          &base::MessageLoop::Quit,
-          base::Unretained(base::MessageLoop::current())));
+      base::MessageLoop::current()->PostTask(
+          FROM_HERE,
+          base::Bind(&base::MessageLoop::QuitWhenIdle,
+                     base::Unretained(base::MessageLoop::current())));
     }
   }
 
diff --git a/chrome/browser/ui/exclusive_access/flash_fullscreen_interactive_browsertest.cc b/chrome/browser/ui/exclusive_access/flash_fullscreen_interactive_browsertest.cc
index d0e6b8c..7c987e1 100644
--- a/chrome/browser/ui/exclusive_access/flash_fullscreen_interactive_browsertest.cc
+++ b/chrome/browser/ui/exclusive_access/flash_fullscreen_interactive_browsertest.cc
@@ -37,7 +37,7 @@ bool RunLoopUntil(const base::Callback<bool()>& condition) {
     }
 
     base::MessageLoop::current()->task_runner()->PostDelayedTask(
-        FROM_HERE, base::MessageLoop::QuitClosure(),
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
         base::TimeDelta::FromMilliseconds(20));
     content::RunMessageLoop();
   }
@@ -228,13 +228,11 @@ class FlashFullscreenInteractiveBrowserTest : public OutOfProcessPPAPITest {
     // |expected_color|.
     bool is_expected_color = false;
     flash_fs_host->CopyFromBackingStore(
-        gfx::Rect(0, 0, 1, 1),
-        gfx::Size(1, 1),
+        gfx::Rect(0, 0, 1, 1), gfx::Size(1, 1),
         base::Bind(
             &FlashFullscreenInteractiveBrowserTest::CheckBitmapForFillColor,
-            expected_color,
-            &is_expected_color,
-            base::MessageLoop::QuitClosure()),
+            expected_color, &is_expected_color,
+            base::MessageLoop::QuitWhenIdleClosure()),
         kN32_SkColorType);
     content::RunMessageLoop();
 
diff --git a/chrome/browser/ui/find_bar/find_bar_host_browsertest.cc b/chrome/browser/ui/find_bar/find_bar_host_browsertest.cc
index a949449..4b32edd 100644
--- a/chrome/browser/ui/find_bar/find_bar_host_browsertest.cc
+++ b/chrome/browser/ui/find_bar/find_bar_host_browsertest.cc
@@ -198,7 +198,7 @@ class FindInPageControllerTest : public InProcessBrowserTest {
     HistoryServiceFactory::GetForProfile(browser()->profile(),
                                          ServiceAccessType::IMPLICIT_ACCESS)
         ->FlushForTest(base::Bind(
-            &base::MessageLoop::Quit,
+            &base::MessageLoop::QuitWhenIdle,
             base::Unretained(base::MessageLoop::current()->current())));
     content::RunMessageLoop();
   }
diff --git a/chrome/browser/ui/omnibox/omnibox_view_browsertest.cc b/chrome/browser/ui/omnibox/omnibox_view_browsertest.cc
index a25b311..ab12bb7 100644
--- a/chrome/browser/ui/omnibox/omnibox_view_browsertest.cc
+++ b/chrome/browser/ui/omnibox/omnibox_view_browsertest.cc
@@ -155,7 +155,7 @@ class OmniboxViewTest : public InProcessBrowserTest,
   // history::HisoryServiceObserver
   void OnHistoryServiceLoaded(
       history::HistoryService* history_service) override {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
  protected:
@@ -369,12 +369,12 @@ class OmniboxViewTest : public InProcessBrowserTest,
       default:
         FAIL() << "Unexpected notification type";
     }
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void OnURLsModified(history::HistoryService* history_service,
                       const history::URLRows& changed_urls) override {
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
  private:
diff --git a/chrome/browser/ui/search/instant_extended_interactive_uitest.cc b/chrome/browser/ui/search/instant_extended_interactive_uitest.cc
index aae0adf..34a519e 100644
--- a/chrome/browser/ui/search/instant_extended_interactive_uitest.cc
+++ b/chrome/browser/ui/search/instant_extended_interactive_uitest.cc
@@ -95,7 +95,9 @@ class QuittingHistoryDBTask : public history::HistoryDBTask {
     return true;
   }
 
-  void DoneRunOnMainThread() override { base::MessageLoop::current()->Quit(); }
+  void DoneRunOnMainThread() override {
+    base::MessageLoop::current()->QuitWhenIdle();
+  }
 
  private:
   ~QuittingHistoryDBTask() override {}
diff --git a/chrome/browser/ui/toolbar/back_forward_menu_model_unittest.cc b/chrome/browser/ui/toolbar/back_forward_menu_model_unittest.cc
index 66c4092..73c76e3 100644
--- a/chrome/browser/ui/toolbar/back_forward_menu_model_unittest.cc
+++ b/chrome/browser/ui/toolbar/back_forward_menu_model_unittest.cc
@@ -46,7 +46,7 @@ class FaviconDelegate : public ui::MenuModelDelegate {
 
   void OnIconChanged(int model_index) override {
     was_called_ = true;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   bool was_called() const { return was_called_; }
diff --git a/chrome/browser/ui/views/frame/browser_window_property_manager_browsertest_win.cc b/chrome/browser/ui/views/frame/browser_window_property_manager_browsertest_win.cc
index ef19840..dc33183 100644
--- a/chrome/browser/ui/views/frame/browser_window_property_manager_browsertest_win.cc
+++ b/chrome/browser/ui/views/frame/browser_window_property_manager_browsertest_win.cc
@@ -48,7 +48,7 @@ namespace {
 void UnblockOnProfileCreation(Profile* profile,
                               Profile::CreateStatus status) {
   if (status == Profile::CREATE_STATUS_INITIALIZED)
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
 }
 
 // Checks that the relaunch name, relaunch command and app icon for the given
@@ -95,7 +95,7 @@ void ValidateBrowserWindowProperties(
                 browser->profile()->GetPath()).value(),
             prop_var.get().pwszVal);
   prop_var.Reset();
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void ValidateHostedAppWindowProperties(const Browser* browser,
@@ -140,7 +140,7 @@ void ValidateHostedAppWindowProperties(const Browser* browser,
                 web_app_dir, base::UTF8ToUTF16(extension->name())).value(),
             prop_var.get().pwszVal);
   prop_var.Reset();
-  base::MessageLoop::current()->Quit();
+  base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void PostValidationTaskToUIThread(const base::Closure& validation_task) {
diff --git a/chrome/browser/ui/views/keyboard_access_browsertest.cc b/chrome/browser/ui/views/keyboard_access_browsertest.cc
index eaa5b47..deb8050 100644
--- a/chrome/browser/ui/views/keyboard_access_browsertest.cc
+++ b/chrome/browser/ui/views/keyboard_access_browsertest.cc
@@ -68,8 +68,8 @@ class ViewFocusChangeWaiter : public views::FocusChangeListener {
   void OnDidChangeFocus(views::View* focused_before,
                         views::View* focused_now) override {
     if (focused_now && focused_now->id() != previous_view_id_) {
-      base::MessageLoop::current()->PostTask(FROM_HERE,
-                                             base::MessageLoop::QuitClosure());
+      base::MessageLoop::current()->PostTask(
+          FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
     }
   }
 
@@ -113,8 +113,7 @@ class SendKeysMenuListener : public views::MenuListener {
     } else {
       SendKeyPress(browser_, ui::VKEY_ESCAPE);
       base::MessageLoop::current()->PostDelayedTask(
-          FROM_HERE,
-          base::MessageLoop::QuitClosure(),
+          FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
           base::TimeDelta::FromMilliseconds(200));
     }
   }
diff --git a/chrome/browser/ui/views/tabs/tab_drag_controller_interactive_uitest.cc b/chrome/browser/ui/views/tabs/tab_drag_controller_interactive_uitest.cc
index 36bca05..337e07b 100644
--- a/chrome/browser/ui/views/tabs/tab_drag_controller_interactive_uitest.cc
+++ b/chrome/browser/ui/views/tabs/tab_drag_controller_interactive_uitest.cc
@@ -96,7 +96,7 @@ class QuitDraggingObserver : public content::NotificationObserver {
                const content::NotificationSource& source,
                const content::NotificationDetails& details) override {
     DCHECK_EQ(chrome::NOTIFICATION_TAB_DRAG_LOOP_DONE, type);
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
     delete this;
   }
 
diff --git a/chrome/browser/ui/views/web_dialog_view_browsertest.cc b/chrome/browser/ui/views/web_dialog_view_browsertest.cc
index 286bcd8..d14883e 100644
--- a/chrome/browser/ui/views/web_dialog_view_browsertest.cc
+++ b/chrome/browser/ui/views/web_dialog_view_browsertest.cc
@@ -57,7 +57,7 @@ class TestWebDialogView : public views::WebDialogView {
       // loop.
       base::MessageLoop::current()->task_runner()->PostTask(
           FROM_HERE,
-          base::Bind(&base::MessageLoop::Quit,
+          base::Bind(&base::MessageLoop::QuitWhenIdle,
                      base::Unretained(base::MessageLoop::current())));
     }
 
diff --git a/chrome/browser/ui/website_settings/mock_permission_bubble_view.cc b/chrome/browser/ui/website_settings/mock_permission_bubble_view.cc
index 7406d13..f4436d6 100644
--- a/chrome/browser/ui/website_settings/mock_permission_bubble_view.cc
+++ b/chrome/browser/ui/website_settings/mock_permission_bubble_view.cc
@@ -54,7 +54,7 @@ void MockPermissionBubbleView::Show(
   permission_requests_ = requests;
   permission_states_ = accept_state;
   if (browser_test_)
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
 }
 
 void MockPermissionBubbleView::Hide() {
diff --git a/chrome/browser/ui/webui/bidi_checker_web_ui_test.cc b/chrome/browser/ui/webui/bidi_checker_web_ui_test.cc
index 522c3e6..cb83a4d 100644
--- a/chrome/browser/ui/webui/bidi_checker_web_ui_test.cc
+++ b/chrome/browser/ui/webui/bidi_checker_web_ui_test.cc
@@ -69,10 +69,9 @@ void ReloadLocaleResourcesOnIOThread(const std::string& new_locale) {
 // crbug.com/95425, crbug.com/132752
 void ReloadLocaleResources(const std::string& new_locale) {
   content::BrowserThread::PostTaskAndReply(
-      content::BrowserThread::IO,
-      FROM_HERE,
+      content::BrowserThread::IO, FROM_HERE,
       base::Bind(&ReloadLocaleResourcesOnIOThread, base::ConstRef(new_locale)),
-      base::MessageLoop::QuitClosure());
+      base::MessageLoop::QuitWhenIdleClosure());
   content::RunMessageLoop();
 }
 
diff --git a/chrome/browser/ui/webui/constrained_web_dialog_ui_browsertest.cc b/chrome/browser/ui/webui/constrained_web_dialog_ui_browsertest.cc
index 33ebfa96..08fec2d 100644
--- a/chrome/browser/ui/webui/constrained_web_dialog_ui_browsertest.cc
+++ b/chrome/browser/ui/webui/constrained_web_dialog_ui_browsertest.cc
@@ -77,7 +77,7 @@ class ConstrainedWebDialogBrowserTest : public InProcessBrowserTest {
       }
 
       base::MessageLoop::current()->task_runner()->PostDelayedTask(
-          FROM_HERE, base::MessageLoop::QuitClosure(),
+          FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
           base::TimeDelta::FromMilliseconds(20));
       content::RunMessageLoop();
     }
diff --git a/chrome/browser/ui/webui/downloads_dom_handler_browsertest.cc b/chrome/browser/ui/webui/downloads_dom_handler_browsertest.cc
index 4eb030b..7c8dcf5 100644
--- a/chrome/browser/ui/webui/downloads_dom_handler_browsertest.cc
+++ b/chrome/browser/ui/webui/downloads_dom_handler_browsertest.cc
@@ -91,18 +91,18 @@ class MockDownloadsDOMHandler : public DownloadsDOMHandler {
   void CallUpdateAll(const base::ListValue& list) override {
     downloads_list_.reset(list.DeepCopy());
     if (waiting_list_) {
-      content::BrowserThread::PostTask(content::BrowserThread::UI,
-                                       FROM_HERE,
-                                       base::MessageLoop::QuitClosure());
+      content::BrowserThread::PostTask(
+          content::BrowserThread::UI, FROM_HERE,
+          base::MessageLoop::QuitWhenIdleClosure());
     }
   }
 
   void CallUpdateItem(const base::DictionaryValue& item) override {
     download_updated_.reset(item.DeepCopy());
     if (waiting_updated_) {
-      content::BrowserThread::PostTask(content::BrowserThread::UI,
-                                       FROM_HERE,
-                                       base::MessageLoop::QuitClosure());
+      content::BrowserThread::PostTask(
+          content::BrowserThread::UI, FROM_HERE,
+          base::MessageLoop::QuitWhenIdleClosure());
     }
   }
 
diff --git a/chrome/browser/ui/webui/local_discovery/local_discovery_ui_browsertest.cc b/chrome/browser/ui/webui/local_discovery/local_discovery_ui_browsertest.cc
index f08f5fe..17e53b8 100644
--- a/chrome/browser/ui/webui/local_discovery/local_discovery_ui_browsertest.cc
+++ b/chrome/browser/ui/webui/local_discovery/local_discovery_ui_browsertest.cc
@@ -289,7 +289,7 @@ class TestMessageLoopCondition {
   void Signal() {
     signaled_ = true;
     if (waiting_)
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
   }
 
   // Pause execution and recursively run the message loop until |Signal()| is
@@ -437,9 +437,9 @@ class LocalDiscoveryUITest : public WebUIBrowserTest {
   }
 
   void RunFor(base::TimeDelta time_period) {
-    base::CancelableCallback<void()> callback(base::Bind(
-        &base::MessageLoop::Quit, base::Unretained(
-            base::MessageLoop::current())));
+    base::CancelableCallback<void()> callback(
+        base::Bind(&base::MessageLoop::QuitWhenIdle,
+                   base::Unretained(base::MessageLoop::current())));
     base::MessageLoop::current()->task_runner()->PostDelayedTask(
         FROM_HERE, callback.callback(), time_period);
 
diff --git a/chrome/browser/ui/webui/web_ui_test_handler.cc b/chrome/browser/ui/webui/web_ui_test_handler.cc
index d4e03aa..a249c1e 100644
--- a/chrome/browser/ui/webui/web_ui_test_handler.cc
+++ b/chrome/browser/ui/webui/web_ui_test_handler.cc
@@ -61,7 +61,7 @@ void WebUITestHandler::HandleTestResult(const base::ListValue* test_result) {
   // Quit the message loop if |is_waiting_| so waiting process can get result or
   // error. To ensure this gets done, do this before ASSERT* calls.
   if (is_waiting_)
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
 
   SCOPED_TRACE("WebUITestHandler::HandleTestResult");
 
@@ -81,7 +81,7 @@ void WebUITestHandler::JavaScriptComplete(const base::Value* result) {
   // Quit the message loop if |is_waiting_| so waiting process can get result or
   // error. To ensure this gets done, do this before ASSERT* calls.
   if (is_waiting_)
-    base::MessageLoopForUI::current()->Quit();
+    base::MessageLoopForUI::current()->QuitWhenIdle();
 
   SCOPED_TRACE("WebUITestHandler::JavaScriptComplete");
 
diff --git a/chrome/common/local_discovery/local_domain_resolver_unittest.cc b/chrome/common/local_discovery/local_domain_resolver_unittest.cc
index f55783e..f34ff2db 100644
--- a/chrome/common/local_discovery/local_domain_resolver_unittest.cc
+++ b/chrome/common/local_discovery/local_domain_resolver_unittest.cc
@@ -81,9 +81,9 @@ class LocalDomainResolverTest : public testing::Test {
   }
 
   void RunFor(base::TimeDelta time_period) {
-    base::CancelableCallback<void()> callback(base::Bind(
-        &base::MessageLoop::Quit,
-        base::Unretained(base::MessageLoop::current())));
+    base::CancelableCallback<void()> callback(
+        base::Bind(&base::MessageLoop::QuitWhenIdle,
+                   base::Unretained(base::MessageLoop::current())));
     base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
         FROM_HERE, callback.callback(), time_period);
 
diff --git a/chrome/common/local_discovery/service_discovery_client_unittest.cc b/chrome/common/local_discovery/service_discovery_client_unittest.cc
index ed6db5c..0b77410 100644
--- a/chrome/common/local_discovery/service_discovery_client_unittest.cc
+++ b/chrome/common/local_discovery/service_discovery_client_unittest.cc
@@ -223,9 +223,7 @@ class ServiceDiscoveryTest : public ::testing::Test {
     callback.Cancel();
   }
 
-  void Stop() {
-    base::MessageLoop::current()->Quit();
-  }
+  void Stop() { base::MessageLoop::current()->QuitWhenIdle(); }
 
   net::MockMDnsSocketFactory socket_factory_;
   net::MDnsClientImpl mdns_client_;
diff --git a/chrome/common/mac/mock_launchd.cc b/chrome/common/mac/mock_launchd.cc
index b4e80ec..3af8aef 100644
--- a/chrome/common/mac/mock_launchd.cc
+++ b/chrome/common/mac/mock_launchd.cc
@@ -226,7 +226,7 @@ CFDictionaryRef MockLaunchd::CopyDictionaryByCheckingIn(CFErrorRef* error) {
 
 bool MockLaunchd::RemoveJob(CFStringRef label, CFErrorRef* error) {
   remove_called_ = true;
-  message_loop_->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+  message_loop_->PostTask(FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   return true;
 }
 
@@ -235,7 +235,7 @@ bool MockLaunchd::RestartJob(Domain domain,
                              CFStringRef name,
                              CFStringRef session_type) {
   restart_called_ = true;
-  message_loop_->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+  message_loop_->PostTask(FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   return true;
 }
 
diff --git a/chrome/common/service_process_util_unittest.cc b/chrome/common/service_process_util_unittest.cc
index 8844f91..1ed68ef 100644
--- a/chrome/common/service_process_util_unittest.cc
+++ b/chrome/common/service_process_util_unittest.cc
@@ -54,7 +54,8 @@ void ShutdownTask(base::MessageLoop* loop) {
   // Quit the main message loop.
   ASSERT_FALSE(g_good_shutdown);
   g_good_shutdown = true;
-  loop->task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+  loop->task_runner()->PostTask(FROM_HERE,
+                                base::MessageLoop::QuitWhenIdleClosure());
 }
 
 }  // namespace
@@ -235,7 +236,7 @@ MULTIPROCESS_TEST_MAIN(ServiceProcessStateTestShutdown) {
       io_thread_.task_runner().get(),
       base::Bind(&ShutdownTask, base::MessageLoop::current())));
   message_loop.task_runner()->PostDelayedTask(
-      FROM_HERE, base::MessageLoop::QuitClosure(),
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
       TestTimeouts::action_max_timeout());
   EXPECT_FALSE(g_good_shutdown);
   message_loop.Run();
@@ -279,8 +280,7 @@ class ServiceProcessStateFileManipulationTest : public ::testing::Test {
     ASSERT_TRUE(service_process_state_.Initialize());
     ASSERT_TRUE(service_process_state_.SignalReady(
         io_thread_.task_runner().get(), base::Closure()));
-    loop_.PostDelayedTask(FROM_HERE,
-                          base::MessageLoop::QuitClosure(),
+    loop_.PostDelayedTask(FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
                           TestTimeouts::action_max_timeout());
   }
 
diff --git a/chrome/common/worker_thread_ticker_unittest.cc b/chrome/common/worker_thread_ticker_unittest.cc
index dbb2e01..5722030 100644
--- a/chrome/common/worker_thread_ticker_unittest.cc
+++ b/chrome/common/worker_thread_ticker_unittest.cc
@@ -21,8 +21,8 @@ class TestCallback : public WorkerThreadTicker::Callback {
     counter_++;
 
     // Finish the test faster.
-    message_loop_->task_runner()->PostTask(FROM_HERE,
-                                           base::MessageLoop::QuitClosure());
+    message_loop_->task_runner()->PostTask(
+        FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   }
 
   int counter() const { return counter_; }
@@ -41,7 +41,7 @@ class LongCallback : public WorkerThreadTicker::Callback {
 
 void RunMessageLoopForAWhile() {
   base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
-      FROM_HERE, base::MessageLoop::QuitClosure(),
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure(),
       base::TimeDelta::FromMilliseconds(500));
   base::MessageLoop::current()->Run();
 }
diff --git a/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc b/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc
index 7896758..b5a9979 100644
--- a/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc
+++ b/chrome/renderer/safe_browsing/phishing_term_feature_extractor_unittest.cc
@@ -121,12 +121,12 @@ class PhishingTermFeatureExtractorTest : public ::testing::Test {
   // Completion callback for feature extraction.
   void ExtractionDone(bool success) {
     success_ = success;
-    msg_loop_.Quit();
+    msg_loop_.QuitWhenIdle();
   }
 
   void QuitExtraction() {
     extractor_->CancelPendingExtraction();
-    msg_loop_.Quit();
+    msg_loop_.QuitWhenIdle();
   }
 
   base::MessageLoop msg_loop_;
diff --git a/chrome/service/cloud_print/cloud_print_url_fetcher_unittest.cc b/chrome/service/cloud_print/cloud_print_url_fetcher_unittest.cc
index 7d7c657..6bc7b37 100644
--- a/chrome/service/cloud_print/cloud_print_url_fetcher_unittest.cc
+++ b/chrome/service/cloud_print/cloud_print_url_fetcher_unittest.cc
@@ -255,7 +255,8 @@ CloudPrintURLFetcherBasicTest::HandleRawResponse(
   if (handle_raw_response_) {
     // If the current message loop is not the IO loop, it will be shut down when
     // the main loop returns and this thread subsequently goes out of scope.
-    io_task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+    io_task_runner()->PostTask(FROM_HERE,
+                               base::MessageLoop::QuitWhenIdleClosure());
     return CloudPrintURLFetcher::STOP_PROCESSING;
   }
   return CloudPrintURLFetcher::CONTINUE_PROCESSING;
@@ -269,7 +270,8 @@ CloudPrintURLFetcherBasicTest::HandleRawData(
   // We should never get here if we returned true in HandleRawResponse
   EXPECT_FALSE(handle_raw_response_);
   if (handle_raw_data_) {
-    io_task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+    io_task_runner()->PostTask(FROM_HERE,
+                               base::MessageLoop::QuitWhenIdleClosure());
     return CloudPrintURLFetcher::STOP_PROCESSING;
   }
   return CloudPrintURLFetcher::CONTINUE_PROCESSING;
@@ -284,7 +286,8 @@ CloudPrintURLFetcherBasicTest::HandleJSONData(
   // We should never get here if we returned true in one of the above methods.
   EXPECT_FALSE(handle_raw_response_);
   EXPECT_FALSE(handle_raw_data_);
-  io_task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+  io_task_runner()->PostTask(FROM_HERE,
+                             base::MessageLoop::QuitWhenIdleClosure());
   return CloudPrintURLFetcher::STOP_PROCESSING;
 }
 
@@ -302,7 +305,8 @@ CloudPrintURLFetcherOverloadTest::HandleRawData(
     // We have already sent 20 requests continuously. And we expect that
     // it takes more than 1 second due to the overload protection settings.
     EXPECT_TRUE(Time::Now() - start_time_ >= one_second);
-    io_task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+    io_task_runner()->PostTask(FROM_HERE,
+                               base::MessageLoop::QuitWhenIdleClosure());
   }
   return CloudPrintURLFetcher::STOP_PROCESSING;
 }
@@ -321,7 +325,8 @@ CloudPrintURLFetcherRetryBackoffTest::HandleRawData(
 void CloudPrintURLFetcherRetryBackoffTest::OnRequestGiveUp() {
   // It takes more than 200 ms to finish all 11 requests.
   EXPECT_TRUE(Time::Now() - start_time_ >= TimeDelta::FromMilliseconds(200));
-  io_task_runner()->PostTask(FROM_HERE, base::MessageLoop::QuitClosure());
+  io_task_runner()->PostTask(FROM_HERE,
+                             base::MessageLoop::QuitWhenIdleClosure());
 }
 
 TEST_F(CloudPrintURLFetcherBasicTest, HandleRawResponse) {
diff --git a/chrome/service/service_process.cc b/chrome/service/service_process.cc
index 0725a54..b2d99dd 100644
--- a/chrome/service/service_process.cc
+++ b/chrome/service/service_process.cc
@@ -264,8 +264,8 @@ void ServiceProcess::Shutdown() {
 }
 
 void ServiceProcess::Terminate() {
-  main_message_loop_->task_runner()->PostTask(FROM_HERE,
-                                              base::MessageLoop::QuitClosure());
+  main_message_loop_->task_runner()->PostTask(
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
 }
 
 void ServiceProcess::OnShutdown() {
diff --git a/chrome/test/base/browser_with_test_window_test.cc b/chrome/test/base/browser_with_test_window_test.cc
index b184e31..97c46ec 100644
--- a/chrome/test/base/browser_with_test_window_test.cc
+++ b/chrome/test/base/browser_with_test_window_test.cc
@@ -105,7 +105,7 @@ void BrowserWithTestWindowTest::TearDown() {
   // A Task is leaked if we don't destroy everything, then run the message
   // loop.
   base::ThreadTaskRunnerHandle::Get()->PostTask(
-      FROM_HERE, base::MessageLoop::QuitClosure());
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   base::MessageLoop::current()->Run();
 }
 
diff --git a/chrome/test/base/in_process_browser_test.h b/chrome/test/base/in_process_browser_test.h
index 9192ec2..06c0b61 100644
--- a/chrome/test/base/in_process_browser_test.h
+++ b/chrome/test/base/in_process_browser_test.h
@@ -51,8 +51,8 @@ class ContentRendererClient;
 //   state changes you'll need to run the message loop from your test method.
 //   For example, if you need to wait till a find bar has completely been shown
 //   you'll need to invoke content::RunMessageLoop. When the message bar is
-//   shown, invoke MessageLoop::current()->Quit() to return control back to your
-//   test method.
+//   shown, invoke MessageLoop::current()->QuitWhenIdle() to return control back
+//   to your test method.
 // . If you subclass and override SetUp, be sure and invoke
 //   InProcessBrowserTest::SetUp. (But see also SetUpOnMainThread,
 //   SetUpInProcessBrowserTestFixture and other related hook methods for a
diff --git a/chrome/test/base/interactive_test_utils_mac.mm b/chrome/test/base/interactive_test_utils_mac.mm
index 17fa8e8..c1c3b10 100644
--- a/chrome/test/base/interactive_test_utils_mac.mm
+++ b/chrome/test/base/interactive_test_utils_mac.mm
@@ -83,7 +83,7 @@ void ClickOnView(const Browser* browser, ViewID vid) {
       view,
       ui_controls::LEFT,
       ui_controls::DOWN | ui_controls::UP,
-      base::MessageLoop::QuitClosure());
+      base::MessageLoop::QuitWhenIdleClosure());
   content::RunMessageLoop();
 }
 
diff --git a/chrome/test/base/interactive_test_utils_views.cc b/chrome/test/base/interactive_test_utils_views.cc
index ac5047f..584ffb8 100644
--- a/chrome/test/base/interactive_test_utils_views.cc
+++ b/chrome/test/base/interactive_test_utils_views.cc
@@ -36,10 +36,9 @@ void ClickOnView(const Browser* browser, ViewID vid) {
   views::View* view =
       BrowserView::GetBrowserViewForBrowser(browser)->GetViewByID(vid);
   DCHECK(view);
-  MoveMouseToCenterAndPress(view,
-                            ui_controls::LEFT,
+  MoveMouseToCenterAndPress(view, ui_controls::LEFT,
                             ui_controls::DOWN | ui_controls::UP,
-                            base::MessageLoop::QuitClosure());
+                            base::MessageLoop::QuitWhenIdleClosure());
   content::RunMessageLoop();
 }
 
diff --git a/chrome/test/base/testing_profile.cc b/chrome/test/base/testing_profile.cc
index f196614..2bef2be 100644
--- a/chrome/test/base/testing_profile.cc
+++ b/chrome/test/base/testing_profile.cc
@@ -141,7 +141,9 @@ class QuittingHistoryDBTask : public history::HistoryDBTask {
     return true;
   }
 
-  void DoneRunOnMainThread() override { base::MessageLoop::current()->Quit(); }
+  void DoneRunOnMainThread() override {
+    base::MessageLoop::current()->QuitWhenIdle();
+  }
 
  private:
   ~QuittingHistoryDBTask() override {}
@@ -560,7 +562,8 @@ void TestingProfile::DestroyHistoryService() {
     return;
 
   history_service->ClearCachedDataForContextID(0);
-  history_service->SetOnBackendDestroyTask(base::MessageLoop::QuitClosure());
+  history_service->SetOnBackendDestroyTask(
+      base::MessageLoop::QuitWhenIdleClosure());
   history_service->Cleanup();
   HistoryServiceFactory::ShutdownForProfile(this);
 
@@ -573,7 +576,7 @@ void TestingProfile::DestroyHistoryService() {
   // Make sure we don't have any event pending that could disrupt the next
   // test.
   base::ThreadTaskRunnerHandle::Get()->PostTask(
-      FROM_HERE, base::MessageLoop::QuitClosure());
+      FROM_HERE, base::MessageLoop::QuitWhenIdleClosure());
   base::MessageLoop::current()->Run();
 }
 
diff --git a/chrome/test/chromedriver/net/websocket_unittest.cc b/chrome/test/chromedriver/net/websocket_unittest.cc
index 2922c7f..4405939 100644
--- a/chrome/test/chromedriver/net/websocket_unittest.cc
+++ b/chrome/test/chromedriver/net/websocket_unittest.cc
@@ -46,7 +46,7 @@ class Listener : public WebSocketListener {
     EXPECT_EQ(messages_[0], message);
     messages_.erase(messages_.begin());
     if (messages_.empty())
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void OnClose() override { EXPECT_TRUE(false); }
diff --git a/chrome/utility/importer/firefox_importer_unittest_utils_mac.cc b/chrome/utility/importer/firefox_importer_unittest_utils_mac.cc
index a1b1c04..445f9df 100644
--- a/chrome/utility/importer/firefox_importer_unittest_utils_mac.cc
+++ b/chrome/utility/importer/firefox_importer_unittest_utils_mac.cc
@@ -78,14 +78,14 @@ class FFDecryptorServerChannelListener : public IPC::Listener {
     DCHECK(!got_result);
     result_bool = result;
     got_result = true;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void OnDecryptedTextResponse(const base::string16& decrypted_text) {
     DCHECK(!got_result);
     result_string = decrypted_text;
     got_result = true;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void OnParseSignonsResponse(
@@ -93,7 +93,7 @@ class FFDecryptorServerChannelListener : public IPC::Listener {
     DCHECK(!got_result);
     result_vector = parsed_vector;
     got_result = true;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void QuitClient() {
@@ -115,7 +115,7 @@ class FFDecryptorServerChannelListener : public IPC::Listener {
   // If an error occured, just kill the message Loop.
   void OnChannelError() override {
     got_result = false;
-    base::MessageLoop::current()->Quit();
+    base::MessageLoop::current()->QuitWhenIdle();
   }
 
   // Results of IPC calls.
@@ -164,7 +164,7 @@ class CancellableQuitMsgLoop : public base::RefCounted<CancellableQuitMsgLoop> {
   CancellableQuitMsgLoop() : cancelled_(false) {}
   void QuitNow() {
     if (!cancelled_)
-      base::MessageLoop::current()->Quit();
+      base::MessageLoop::current()->QuitWhenIdle();
   }
   bool cancelled_;
 
@@ -256,9 +256,7 @@ class FFDecryptorClientChannelListener : public IPC::Listener {
     sender_->Send(new Msg_ParseSignons_Response(forms));
   }
 
-  void OnQuitRequest() {
-    base::MessageLoop::current()->Quit();
-  }
+  void OnQuitRequest() { base::MessageLoop::current()->QuitWhenIdle(); }
 
   bool OnMessageReceived(const IPC::Message& msg) override {
     bool handled = true;
@@ -272,7 +270,9 @@ class FFDecryptorClientChannelListener : public IPC::Listener {
     return handled;
   }
 
-  void OnChannelError() override { base::MessageLoop::current()->Quit(); }
+  void OnChannelError() override {
+    base::MessageLoop::current()->QuitWhenIdle();
+  }
 
  private:
   NSSDecryptor decryptor_;