Notify page load metrics when the app enters the background.

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.
 
 {
   'variables': {
     # All .cc, .h, .m, and .mm files under browser except for:
     # * tests and mocks.
     # * code below browser/chromeos
     # * code below browser/extensions
@@ skipping 1020 matching lines @@
       'browser/media/android/router/media_router_dialog_controller_android.cc',
       'browser/media/android/router/media_router_dialog_controller_android.h',
       'browser/media/media_stream_infobar_delegate_android.cc',
       'browser/media/media_stream_infobar_delegate_android.h',
       'browser/media/midi_permission_infobar_delegate_android.cc',
       'browser/media/midi_permission_infobar_delegate_android.h',
       'browser/media/protected_media_identifier_infobar_delegate_android.cc',
       'browser/media/protected_media_identifier_infobar_delegate_android.h',
       'browser/metrics/android_metrics_provider.cc',
       'browser/metrics/android_metrics_provider.h',
+      'browser/metrics/page_load_metrics_provider.cc',
+      'browser/metrics/page_load_metrics_provider.h',
       'browser/net/spdyproxy/data_reduction_promo_infobar_delegate_android.cc',
       'browser/net/spdyproxy/data_reduction_promo_infobar_delegate_android.h',
       'browser/net/spdyproxy/data_reduction_proxy_settings_android.cc',
       'browser/net/spdyproxy/data_reduction_proxy_settings_android.h',
       'browser/password_manager/account_chooser_dialog_android.cc',
       'browser/password_manager/account_chooser_dialog_android.h',
       'browser/password_manager/auto_signin_first_run_dialog_android.cc',
       'browser/password_manager/auto_signin_first_run_dialog_android.h',
       'browser/password_manager/credential_android.cc',
       'browser/password_manager/credential_android.h',
@@ skipping 3293 matching lines @@
             '../components/components.gyp:rlz',
             '../components/components.gyp:search_engines',
             '../rlz/rlz.gyp:rlz_lib',
             'common',
           ],
         },
       ],
     }],
   ],
 }