components: Introduce AlarmTimer class and use it for GCM heartbeat

google_apis/gcm/gcm.gyp

 # Copyright 2013 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,
   },
 
   'targets': [
@@ skipping 63 matching lines @@
         'engine/unregistration_request.cc',
         'engine/unregistration_request.h',
         'monitoring/gcm_stats_recorder.h',
         'protocol/android_checkin.proto',
         'protocol/checkin.proto',
         'protocol/mcs.proto',
       ],
       'includes': [
         '../../build/protoc.gypi'
       ],
+      'conditions': [
+        ['chromeos == 1', {
+          'dependencies': [
+            '../../components/components.gyp:timer',
+          ],
+        }],
+      ],
     },
 
     # The test support library that is needed to test gcm.
     {
       # GN version: //google_apis/gcm:test_support
       'target_name': 'gcm_test_support',
       'type': 'static_library',
       'include_dirs': [
         '..',
       ],
@@ skipping 74 matching lines @@
         'engine/gcm_store_impl_unittest.cc',
         'engine/gservices_settings_unittest.cc',
         'engine/heartbeat_manager_unittest.cc',
         'engine/mcs_client_unittest.cc',
         'engine/registration_request_unittest.cc',
         'engine/unregistration_request_unittest.cc',
       ]
     },
   ],
 }