[Background Sync] Use GcmNetworkManager to start the browser for sync events.

chrome/browser/background_sync/background_sync_controller_impl.h

 // Copyright 2015 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_SYNC_BACKGROUND_SYNC_CONTROLLER_IMPL_H_
 #define CHROME_BROWSER_BACKGROUND_SYNC_BACKGROUND_SYNC_CONTROLLER_IMPL_H_
 
 #include "content/public/browser/background_sync_controller.h"
 
 #include "components/keyed_service/core/keyed_service.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace rappor {
 class RapporService;
 }
 
 class Profile;
 
 class BackgroundSyncControllerImpl : public content::BackgroundSyncController,
                                      public KeyedService {
  public:
   explicit BackgroundSyncControllerImpl(Profile* profile);
   ~BackgroundSyncControllerImpl() override;
 
   // content::BackgroundSyncController overrides.
   void NotifyBackgroundSyncRegistered(const GURL& origin) override;
 
+#if defined(OS_ANDROID)
+  void LaunchBrowserWhenNextOnline(
+      const content::BackgroundSyncManager* registrant,
+      bool launch_when_next_online) override;
+#endif
+
  protected:
   // Virtual for testing.
   virtual rappor::RapporService* GetRapporService();
 
  private:
   Profile* profile_;  // This object is owned by profile_.
 
   DISALLOW_COPY_AND_ASSIGN(BackgroundSyncControllerImpl);
 };
 
 #endif  // CHROME_BROWSER_BACKGROUND_SYNC_BACKGROUND_SYNC_CONTROLLER_IMPL_H_