PerformanceMonitor: UMA alert for high browser CPU usage.

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 1325 matching lines @@
         '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',
         'browser/performance_monitor/performance_monitor.cc',
         'browser/performance_monitor/performance_monitor.h',
         'browser/performance_monitor/performance_monitor_util.cc',
         'browser/performance_monitor/performance_monitor_util.h',
+        'browser/performance_monitor/process_metrics_history.cc',
+        'browser/performance_monitor/process_metrics_history.h',
         'browser/performance_monitor/startup_timer.cc',
         'browser/performance_monitor/startup_timer.h',
         'browser/platform_util.h',
         'browser/platform_util_android.cc',
         'browser/platform_util_aura.cc',
         'browser/platform_util_chromeos.cc',
         'browser/platform_util_common_linux.cc',
         'browser/platform_util_linux.cc',
         'browser/platform_util_mac.mm',
         'browser/platform_util_win.cc',
@@ skipping 2223 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' ],
         },
       ],
      },
     ],
   ],
 }