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

content/content.gyp

 # 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.
 
 {
   'variables': {
     'chromium_code': 1,  # Use higher warning level.
     'chromium_enable_vtune_jit_for_v8%': 0,  # enable the vtune support for V8 engine.
     'directxsdk_exists': '<!pymod_do_main(dir_exists ../third_party/directxsdk)',
   },
@@ skipping 424 matching lines @@
             '../media/media.gyp:media_java',
             '../mojo/mojo_base.gyp:mojo_application_bindings',
             '../mojo/mojo_base.gyp:mojo_system_java',
             '../net/net.gyp:net',
             '../skia/skia.gyp:skia_mojo',
             '../third_party/mojo/mojo_public.gyp:mojo_bindings_java',
             '../ui/android/ui_android.gyp:ui_java',
             '../ui/touch_selection/ui_touch_selection.gyp:selection_event_type_java',
             '../ui/touch_selection/ui_touch_selection.gyp:touch_handle_orientation_java',
             '../third_party/android_tools/android_tools.gyp:android_support_v13_javalib',
+            '../third_party/android_tools/android_tools.gyp:google_play_services_javalib',
             '../third_party/WebKit/public/blink_headers.gyp:blink_headers_java',
             '../ui/mojo/geometry/mojo_bindings.gyp:mojo_geometry_bindings',
             'common_aidl',
             'console_message_level_java',
             'content_common',
             'content_strings_grd',
             'content_gamepad_mapping',
             'gesture_event_type_java',
             'invalidate_types_java',
             'navigation_controller_java',
@@ skipping 188 matching lines @@
                   ],
                 },
               ],
             }],
           ],
         },
       ],
     }],  # OS == "android"
   ],
 }