components: Introduce AlarmTimer class and use it for GCM heartbeat

base/base.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,
   },
   'includes': [
     '../build/win_precompile.gypi',
@@ skipping 605 matching lines @@
         'threading/thread_id_name_manager_unittest.cc',
         'threading/thread_local_storage_unittest.cc',
         'threading/thread_local_unittest.cc',
         'threading/thread_unittest.cc',
         'threading/watchdog_unittest.cc',
         'threading/worker_pool_posix_unittest.cc',
         'threading/worker_pool_unittest.cc',
         'time/pr_time_unittest.cc',
         'time/time_unittest.cc',
         'time/time_win_unittest.cc',
+        'timer/alarm_timer_unittest.cc',
         'timer/hi_res_timer_manager_unittest.cc',
         'timer/mock_timer_unittest.cc',
         'timer/timer_unittest.cc',
         'tools_sanity_unittest.cc',
         'tracked_objects_unittest.cc',
         'tuple_unittest.cc',
         'values_unittest.cc',
         'version_unittest.cc',
         'vlog_unittest.cc',
         'win/dllmain.cc',
@@ skipping 852 matching lines @@
               'dependencies': [
                 '../tools/xdisplaycheck/xdisplaycheck.gyp:xdisplaycheck',
               ],
             }],
           ],
         },
       ],
     }],
   ],
 }