Define PushMessagingApplicationId and replace ad-hoc code.

chrome/chrome_tests_unit.gypi

 # Copyright 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.
 {
   'targets': [
     {
       # This target contains mocks and test utilities that don't belong in
       # production libraries but are used by more than one test executable.
       'target_name': 'test_support_common',
       'type': 'static_library',
@@ skipping 1283 matching lines @@
         'browser/search_engines/search_provider_install_data_unittest.cc',
         'browser/search_engines/template_url_fetcher_unittest.cc',
         'browser/search_engines/template_url_parser_unittest.cc',
         'browser/search_engines/template_url_service_sync_unittest.cc',
         'browser/search_engines/template_url_service_unittest.cc',
         'browser/search_engines/template_url_scraper_unittest.cc',
         'browser/services/gcm/fake_signin_manager.cc',
         'browser/services/gcm/fake_signin_manager.h',
         'browser/services/gcm/gcm_account_tracker_unittest.cc',
         'browser/services/gcm/gcm_profile_service_unittest.cc',
+        'browser/services/gcm/push_messaging_application_id_unittest.cc',
         'browser/sessions/persistent_tab_restore_service_unittest.cc',
         'browser/sessions/restore_on_startup_policy_handler_unittest.cc',
         'browser/sessions/session_backend_unittest.cc',
         'browser/sessions/session_service_unittest.cc',
         'browser/sessions/session_types_unittest.cc',
         'browser/shell_integration_linux_unittest.cc',
         'browser/shell_integration_win_unittest.cc',
         'browser/signin/account_reconcilor_unittest.cc',
         'browser/signin/account_service_flag_fetcher_unittest.cc',
         'browser/signin/local_auth_unittest.cc',
@@ skipping 1615 matching lines @@
               'dependencies': [
                 '../tools/xdisplaycheck/xdisplaycheck.gyp:xdisplaycheck',
               ],
             }],
           ],
         },
       ],
     }],
   ],  # 'conditions'
 }