Make UpgradeDetector listen to VariationsService changes.

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 1805 matching lines @@
         'browser/ui/webui/signin/login_ui_service_unittest.cc',
         'browser/ui/webui/sync_setup_handler_unittest.cc',
         'browser/ui/webui/theme_source_unittest.cc',
         'browser/ui/webui/web_dialog_web_contents_delegate_unittest.cc',
         'browser/ui/window_sizer/window_sizer_ash_unittest.cc',
         'browser/ui/window_sizer/window_sizer_common_unittest.cc',
         'browser/ui/window_sizer/window_sizer_unittest.cc',
         'browser/ui/zoom/zoom_controller_unittest.cc',
         'browser/undo/bookmark_undo_service_test.cc',
         'browser/undo/undo_manager_test.cc',
+        'browser/upgrade_detector_impl_unittest.cc',
         'browser/upload_list_unittest.cc',
         'browser/web_applications/web_app_mac_unittest.mm',
         'browser/web_applications/web_app_unittest.cc',
         'browser/web_resource/eula_accepted_notifier_unittest.cc',
         'browser/web_resource/promo_resource_service_mobile_ntp_unittest.cc',
         'browser/web_resource/promo_resource_service_unittest.cc',
         'browser/web_resource/resource_request_allowed_notifier_test_util.cc',
         'browser/web_resource/resource_request_allowed_notifier_test_util.h',
         'browser/web_resource/resource_request_allowed_notifier_unittest.cc',
         'browser/webdata/keyword_table_unittest.cc',
@@ skipping 1079 matching lines @@
               'dependencies': [
                 '../tools/xdisplaycheck/xdisplaycheck.gyp:xdisplaycheck',
               ],
             }],
           ],
         },
       ],
     }],
   ],  # 'conditions'
 }