Add BackgroundModeOptimizer that can restart the browser

chrome/browser/background/background_mode_manager.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_BACKGROUND_BACKGROUND_MODE_MANAGER_H_
 #define CHROME_BROWSER_BACKGROUND_BACKGROUND_MODE_MANAGER_H_
 
 #include <map>
 #include <set>
 #include <vector>
 
 #include "base/callback_forward.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/scoped_vector.h"
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/background/background_application_list_model.h"
 #include "chrome/browser/lifetime/scoped_keep_alive.h"
 #include "chrome/browser/profiles/profile_attributes_storage.h"
 #include "chrome/browser/status_icons/status_icon.h"
 #include "chrome/browser/status_icons/status_icon_menu_model.h"
 #include "chrome/browser/ui/browser_list_observer.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "components/prefs/pref_change_registrar.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "extensions/common/extension_id.h"
 
+class BackgroundModeOptimizer;
 class BackgroundTrigger;
 class Browser;
 class PrefRegistrySimple;
 class Profile;
 class StatusIcon;
 class StatusTray;
 
 namespace base {
 class CommandLine;
 }
@@ skipping 33 matching lines @@
 
   virtual void RegisterProfile(Profile* profile);
 
   static void LaunchBackgroundApplication(Profile* profile,
       const extensions::Extension* extension);
 
   // Gets a browser window for |profile| associated with the active desktop.
   // Opens a new browser window if there isn't one for the active desktop.
   static Browser* GetBrowserWindowForProfile(Profile* profile);
 
+  // Getter and setter for the flag indicating whether Chrome should start in
+  // background mode the next time.
+  static bool ShouldRestartInBackground();

[sky, 2016/07/06 16:55:33]

nit: inline these are these are trivially.

[dgn, 2016/07/22 15:18:09]

Done.

+  static void SetShouldRestartInBackground(bool enable);
+
   // Returns true if background mode is active.
   virtual bool IsBackgroundModeActive();
 
   // Suspends background mode until either ResumeBackgroundMode is called or
   // Chrome is restarted. This has the same effect as ending background mode
   // for the current browser session.
   virtual void SuspendBackgroundMode();
 
   // Resumes background mode. This ends a suspension of background mode, but
   // will not start it if it is not enabled.
@@ skipping 215 matching lines @@
   virtual void EnableLaunchOnStartup(bool should_launch);
 
   // Invoked when a client is installed so we can display a platform-specific
   // notification.
   virtual void DisplayClientInstalledNotification(const base::string16& name);
 
   // Invoked to put Chrome in KeepAlive mode - chrome runs in the background
   // and has a status bar icon.
   void StartBackgroundMode();
 
-  // Invoked to take Chrome out of KeepAlive mode - chrome stops running in
+  // Invoked to take Chrome out of KeepAlive mode - Chrome stops running in
   // the background and removes its status bar icon.
   void EndBackgroundMode();
 
   // Enables keep alive and the status tray icon if and only if background mode
   // is active and not suspended.
   virtual void UpdateKeepAliveAndTrayIcon();
 
   // Release keep_alive_for_startup_. This is invoked as a callback to make
   // make sure the message queue was initialized before we attempt to exit.
   void ReleaseStartupKeepAliveCallback();
@@ skipping 54 matching lines @@
   // Returns the number of pending triggers in the system, for all profiles.
   int GetPendingTriggerCount() const;
 
   // Returns true if we should be in background mode.
   bool ShouldBeInBackgroundMode() const;
 
   // Finds the BackgroundModeData associated with the last active profile,
   // if the profile isn't locked. Returns NULL otherwise.
   BackgroundModeData* GetBackgroundModeDataForLastProfile() const;
 
+  // Set to true when the next restart should be done in background mode.
+  // Static because its value is read after the background mode manager is
+  // destroyed.
+  static bool should_restart_in_background_;
+
   // Reference to the ProfileAttributesStorage. It is used to update the
   // background app status of profiles when they open/close background apps.
   ProfileAttributesStorage* profile_storage_;
 
   // Registrars for managing our change observers.
   content::NotificationRegistrar registrar_;
   PrefChangeRegistrar pref_registrar_;
 
   // The profile-keyed data for this background mode manager. Keyed on profile.
   BackgroundModeInfoMap background_mode_data_;
@@ skipping 22 matching lines @@
 
   // Background mode does not always keep Chrome alive. When it does, it is
   // using this scoped object.
   std::unique_ptr<ScopedKeepAlive> keep_alive_;
 
   // Set when we are keeping chrome running during the startup process - this
   // is required when running with the --no-startup-window flag, as otherwise
   // chrome would immediately exit due to having no open windows.
   std::unique_ptr<ScopedKeepAlive> keep_alive_for_startup_;
 
+  // Reference to the optimizer to use to reduce Chrome's footprint when in
+  // background mode. If null, optimizations are disabled.
+  std::unique_ptr<BackgroundModeOptimizer> optimizer_;
+
   // Set to true when Chrome is running with the --keep-alive-for-test flag
   // (used for testing background mode without having to install a background
   // app).
   bool keep_alive_for_test_;
 
   // Set to true when background mode is suspended.
   bool background_mode_suspended_;
 
   base::WeakPtrFactory<BackgroundModeManager> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BackgroundModeManager);
 };
 
 #endif  // CHROME_BROWSER_BACKGROUND_BACKGROUND_MODE_MANAGER_H_