[Password Manager] Add UMA stats to track interaction with synced accounts.

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 857 matching lines @@
       'browser/password_manager/password_store_factory.h',
       'browser/password_manager/password_store_mac.cc',
       'browser/password_manager/password_store_mac.h',
       'browser/password_manager/password_store_mac_internal.h',
       'browser/password_manager/password_store_win.cc',
       'browser/password_manager/password_store_win.h',
       'browser/password_manager/password_store_x.cc',
       'browser/password_manager/password_store_x.h',
       'browser/password_manager/save_password_infobar_delegate.cc',
       'browser/password_manager/save_password_infobar_delegate.h',
+      'browser/password_manager/sync_metrics.cc',
+      'browser/password_manager/sync_metrics.h',
       'browser/performance_monitor/constants.cc',
       'browser/performance_monitor/constants.h',
       'browser/performance_monitor/database.cc',
       'browser/performance_monitor/database.h',
       'browser/performance_monitor/event.cc',
       'browser/performance_monitor/event.h',
       'browser/performance_monitor/key_builder.cc',
       'browser/performance_monitor/key_builder.h',
       'browser/performance_monitor/metric.cc',
       'browser/performance_monitor/metric.h',
@@ skipping 2719 matching lines @@
             'package_name': 'org/chromium/chrome/browser',
             'template_deps': ['browser/android/tab_load_status.h'],
           },
           'includes': [ '../build/android/java_cpp_template.gypi' ],
         },
       ],
      },
     ],
   ],
 }