Make --keep-alive-for-test respect the kBackgroundModeEnabled flag.

chrome/browser/background/background_mode_manager.h

Index: chrome/browser/background/background_mode_manager.h
diff --git a/chrome/browser/background/background_mode_manager.h b/chrome/browser/background/background_mode_manager.h
index e38f5e0c7ef49d99ae3d91a1568077c1fef9c774..a52328d12169dd850c41b10bf048b0df5f89433f 100644
--- a/chrome/browser/background/background_mode_manager.h
+++ b/chrome/browser/background/background_mode_manager.h
@@ -74,6 +74,10 @@ class BackgroundModeManager
   FRIEND_TEST_ALL_PREFIXES(BackgroundModeManagerTest,
                            BackgroundAppInstallUninstallWhileDisabled);
   FRIEND_TEST_ALL_PREFIXES(BackgroundModeManagerTest,
+                           BackgroundModeDisabledPreventsKeepAliveOnStartup);
+  FRIEND_TEST_ALL_PREFIXES(BackgroundModeManagerTest,
+                           DisableBackgroundModeUnderTestFlag);
+  FRIEND_TEST_ALL_PREFIXES(BackgroundModeManagerTest,
                            EnableAfterBackgroundAppInstall);
   FRIEND_TEST_ALL_PREFIXES(BackgroundModeManagerTest,
                            MultiProfile);
@@ -154,6 +158,9 @@ class BackgroundModeManager
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
 
+  // Called when the kBackgroundModeEnabled preference changes.
+  void OnBackgroundModeEnabledPrefChanged();
+
   // BackgroundApplicationListModel::Observer implementation.
   virtual void OnApplicationDataChanged(const extensions::Extension* extension,
                                         Profile* profile) OVERRIDE;
@@ -256,6 +263,9 @@ class BackgroundModeManager
   // Returns the number of background apps for a profile.
   virtual int GetBackgroundAppCountForProfile(Profile* const profile) const;
 
+  // Returns true if we should be in background mode.
+  bool ShouldBeInBackgroundMode() const;
+
   // Reference to the profile info cache. It is used to update the background
   // app status of profiles when they open/close background apps.
   ProfileInfoCache* profile_cache_;