SystemMonitor refactoring: move power state monitor into a separate class called PowerMonitor

content/browser/browser_main_loop.h

Index: content/browser/browser_main_loop.h
diff --git a/content/browser/browser_main_loop.h b/content/browser/browser_main_loop.h
index 25e15a04c1fc03ced8f13b5487642df84edea712..748ca0f3eb60819802bc836ce4a39f54ba3e5ccd 100644
--- a/content/browser/browser_main_loop.h
+++ b/content/browser/browser_main_loop.h
@@ -14,6 +14,7 @@ class HighResolutionTimerManager;
 class MessageLoop;
 
 namespace base {
+class PowerMonitor;
 class SystemMonitor;
 }
 
@@ -95,6 +96,7 @@ class BrowserMainLoop {
   // Members initialized in |MainMessageLoopStart()| ---------------------------
   scoped_ptr<MessageLoop> main_message_loop_;
   scoped_ptr<base::SystemMonitor> system_monitor_;
+  scoped_ptr<base::PowerMonitor> power_monitor_;
   scoped_ptr<HighResolutionTimerManager> hi_res_timer_manager_;
   scoped_ptr<net::NetworkChangeNotifier> network_change_notifier_;
   scoped_ptr<media::AudioManager> audio_manager_;