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

base/power_monitor/power_monitor_posix.cc

Index: base/power_monitor/power_monitor_posix.cc
diff --git a/base/system_monitor/system_monitor_posix.cc b/base/power_monitor/power_monitor_posix.cc
similarity index 55%
rename from base/system_monitor/system_monitor_posix.cc
rename to base/power_monitor/power_monitor_posix.cc
index 6cf01bfee85f6b9e8c71fa5f784c1dc56541ce80..9ae1f89f0e3993c9c8085473b4724b33f9eecb5a 100644
--- a/base/system_monitor/system_monitor_posix.cc
+++ b/base/power_monitor/power_monitor_posix.cc
@@ -2,11 +2,19 @@
 // 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 {
 
-bool SystemMonitor::IsBatteryPower() {
+#if !defined(OS_MACOSX)
+void PowerMonitor::PlatformInit() {
+}
+
+void PowerMonitor::PlatformDestroy() {
+}
+#endif
+
+bool PowerMonitor::IsBatteryPower() {
   NOTIMPLEMENTED();
   return false;
 }