Created multi-process-friendly PowerMonitor interface.

content/common/power_monitor_message_broadcaster.h

+// Copyright 2013 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.
+
+#ifndef CONTENT_COMMON_POWER_MONITOR_MESSAGE_BROADCASTER_H_
+#define CONTENT_COMMON_POWER_MONITOR_MESSAGE_BROADCASTER_H_
+
+#include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
+#include "base/power_monitor/power_observer.h"
+
+#include "content/common/content_export.h"
+
+namespace IPC {
+  class Sender;
+}
+
+namespace content {
+
+// A class used to monitor the power state change and notify the observers about

[vandebo (ex-Chrome), 2013/06/26 21:40:33]

nit: update comment re ...notify the observers...

+// the change event.
+class CONTENT_EXPORT PowerMonitorMessageBroadcaster
+    : public base::PowerObserver {
+public:
+  PowerMonitorMessageBroadcaster(IPC::Sender* sender);
+  virtual ~PowerMonitorMessageBroadcaster();
+
+  // Implement PowerObserver.
+  virtual void OnPowerStateChange(bool on_battery_power) OVERRIDE;
+  virtual void OnSuspend() OVERRIDE;
+  virtual void OnResume() OVERRIDE;
+
+private:
+  IPC::Sender* sender_;
+
+  DISALLOW_COPY_AND_ASSIGN(PowerMonitorMessageBroadcaster);
+};
+
+}  // namespace base
+
+#endif  // CONTENT_COMMON_POWER_MONITOR_CLIENT_H_