[Background Sync] Gather UMA data for Background Sync

content/content_browser.gypi

 # 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.
 
 {
   'dependencies': [
     '../base/base.gyp:base_static',
     '../crypto/crypto.gyp:crypto',
     '../device/battery/battery.gyp:device_battery',
     '../device/battery/battery.gyp:device_battery_mojo_bindings',
@@ skipping 443 matching lines @@
       'browser/appcache/appcache_working_set.cc',
       'browser/appcache/appcache_working_set.h',
       'browser/appcache/chrome_appcache_service.cc',
       'browser/appcache/chrome_appcache_service.h',
       'browser/appcache/view_appcache_internals_job.cc',
       'browser/appcache/view_appcache_internals_job.h',
       'browser/background_sync/background_sync_context_impl.cc',
       'browser/background_sync/background_sync_context_impl.h',
       'browser/background_sync/background_sync_manager.cc',
       'browser/background_sync/background_sync_manager.h',
+      'browser/background_sync/background_sync_metrics.cc',
+      'browser/background_sync/background_sync_metrics.h',
       'browser/background_sync/background_sync_network_observer.cc',
       'browser/background_sync/background_sync_network_observer.h',
       'browser/background_sync/background_sync_power_observer.cc',
       'browser/background_sync/background_sync_power_observer.h',
       'browser/background_sync/background_sync_registration.cc',
       'browser/background_sync/background_sync_registration.h',
       'browser/background_sync/background_sync_registration_options.cc',
       'browser/background_sync/background_sync_registration_options.h',
       'browser/background_sync/background_sync_service_impl.cc',
       'browser/background_sync/background_sync_service_impl.h',
@@ skipping 1633 matching lines @@
       'sources': [
         'browser/vr/vr_device.cc',
         'browser/vr/vr_device.h',
         'browser/vr/vr_device_manager.cc',
         'browser/vr/vr_device_manager.h',
         'browser/vr/vr_device_provider.h',
       ]
     }],
   ],
 }