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

base/power_monitor/power_monitor_win.cc

Index: base/power_monitor/power_monitor_win.cc
diff --git a/base/system_monitor/system_monitor_win.cc b/base/power_monitor/power_monitor_win.cc
similarity index 85%
rename from base/system_monitor/system_monitor_win.cc
rename to base/power_monitor/power_monitor_win.cc
index a8cd54a6db1b8e27716e9b489650c30e8ce849ec..112692c38829eb8e9bbb87f40b2b2f17dd6e74ff 100644
--- a/base/system_monitor/system_monitor_win.cc
+++ b/base/power_monitor/power_monitor_win.cc
@@ -2,11 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "base/system_monitor/system_monitor.h"
+#include "base/power_monitor/power_monitor.h"
 
 namespace base {
 
-void SystemMonitor::ProcessWmPowerBroadcastMessage(int event_id) {
+void PowerMonitor::ProcessWmPowerBroadcastMessage(int event_id) {
   PowerEvent power_event;
   switch (event_id) {
     case PBT_APMPOWERSTATUSCHANGE:  // The power status changed.
@@ -33,12 +33,18 @@ void SystemMonitor::ProcessWmPowerBroadcastMessage(int event_id) {
     // PBT_APMRESUMECRITICAL - removed in Vista.
     // PBT_POWERSETTINGCHANGE - user changed the power settings.
   }
-  ProcessPowerMessage(power_event);
+  ProcessPowerEvent(power_event);
+}
+
+void PowerMonitor::PlatformInit() {
+}
+
+void PowerMonitor::PlatformDestroy() {
 }
 
 // Function to query the system to see if it is currently running on
 // battery power.  Returns true if running on battery.
-bool SystemMonitor::IsBatteryPower() {
+bool PowerMonitor::IsBatteryPower() {
   SYSTEM_POWER_STATUS status;
   if (!GetSystemPowerStatus(&status)) {
     DLOG(ERROR) << "GetSystemPowerStatus failed: " << GetLastError();