Allow PowerMonitorDeviceSource to be used from sequenced tasks.

base/power_monitor/power_monitor_device_source.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 BASE_POWER_MONITOR_POWER_MONITOR_DEVICE_SOURCE_H_
 #define BASE_POWER_MONITOR_POWER_MONITOR_DEVICE_SOURCE_H_
 
 #include "base/base_export.h"
 #include "base/macros.h"
-#include "base/memory/ref_counted.h"
-#include "base/observer_list_threadsafe.h"
 #include "base/power_monitor/power_monitor_source.h"
 #include "base/power_monitor/power_observer.h"
 #include "build/build_config.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #endif  // !OS_WIN
 
 #if defined(OS_IOS)
 #include <objc/runtime.h>
@@ skipping 69 matching lines @@
 #if defined(OS_WIN)
   PowerMessageWindow power_message_window_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(PowerMonitorDeviceSource);
 };
 
 }  // namespace base
 
 #endif  // BASE_POWER_MONITOR_POWER_MONITOR_DEVICE_SOURCE_H_