Add UMA histogram data representing the Synced Notifications feature.

chrome/chrome_browser.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': [
     {
       'target_name': 'browser',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 1319 matching lines @@
         'browser/notifications/sync_notifier/chrome_notifier_delegate.cc',
         'browser/notifications/sync_notifier/chrome_notifier_delegate.h',
         'browser/notifications/sync_notifier/chrome_notifier_service.cc',
         'browser/notifications/sync_notifier/chrome_notifier_service.h',
         'browser/notifications/sync_notifier/chrome_notifier_service_factory.cc',
         'browser/notifications/sync_notifier/chrome_notifier_service_factory.h',
         'browser/notifications/sync_notifier/notification_bitmap_fetcher.cc',
         'browser/notifications/sync_notifier/notification_bitmap_fetcher.h',
         'browser/notifications/sync_notifier/synced_notification.cc',
         'browser/notifications/sync_notifier/synced_notification.h',
+        'browser/notifications/sync_notifier/synced_notification_stats.cc',
+        'browser/notifications/sync_notifier/synced_notification_stats.h',
         'browser/omnibox/omnibox_field_trial.cc',
         'browser/omnibox/omnibox_field_trial.h',
         'browser/omnibox/omnibox_log.cc',
         'browser/omnibox/omnibox_log.h',
         'browser/parsers/metadata_parser.cc',
         'browser/parsers/metadata_parser.h',
         'browser/parsers/metadata_parser_factory.h',
         'browser/parsers/metadata_parser_filebase.cc',
         'browser/parsers/metadata_parser_filebase.h',
         'browser/parsers/metadata_parser_jpeg.cc',
@@ skipping 2346 matching lines @@
             'package_name': 'org/chromium/chrome/browser/ui/toolbar',
             'template_deps': ['browser/ui/toolbar/toolbar_model_security_level_list.h'],
           },
           'includes': [ '../build/android/java_cpp_template.gypi' ],
         },
       ],
      },
     ],
   ],
 }