Update {virtual,override,final} to follow C++11 style chrome/browser/ui.

chrome/browser/ui/ash/volume_controller_chromeos.h

 // Copyright (c) 2012 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 CHROME_BROWSER_UI_ASH_VOLUME_CONTROLLER_CHROMEOS_H_
 #define CHROME_BROWSER_UI_ASH_VOLUME_CONTROLLER_CHROMEOS_H_
 
 #include "ash/volume_control_delegate.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "chromeos/audio/cras_audio_handler.h"
 
 // A class which controls volume when F8-10 or a multimedia key for volume is
 // pressed.
 class VolumeController : public ash::VolumeControlDelegate,
                          public chromeos::CrasAudioHandler::AudioObserver {
  public:
   VolumeController();
-  virtual ~VolumeController();
+  ~VolumeController() override;
 
   // Overridden from ash::VolumeControlDelegate:
-  virtual void HandleVolumeMute(const ui::Accelerator& accelerator) override;
-  virtual void HandleVolumeDown(const ui::Accelerator& accelerator) override;
-  virtual void HandleVolumeUp(const ui::Accelerator& accelerator) override;
+  void HandleVolumeMute(const ui::Accelerator& accelerator) override;
+  void HandleVolumeDown(const ui::Accelerator& accelerator) override;
+  void HandleVolumeUp(const ui::Accelerator& accelerator) override;
 
   // Overridden from chromeos::CrasAudioHandler::AudioObserver.
-  virtual void OnOutputVolumeChanged() override;
-  virtual void OnOutputMuteChanged() override;
+  void OnOutputVolumeChanged() override;
+  void OnOutputMuteChanged() override;
 
  private:
 
   DISALLOW_COPY_AND_ASSIGN(VolumeController);
 };
 
 #endif  // CHROME_BROWSER_UI_ASH_VOLUME_CONTROLLER_CHROMEOS_H_