Update {virtual,override,final} to follow C++11 style in ash.

ash/system/chromeos/audio/audio_detailed_view.h

 // Copyright 2014 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 ASH_SYSTEM_CHROMEOS_AUDIO_AUDIO_DETAILED_VIEW_H_
 #define ASH_SYSTEM_CHROMEOS_AUDIO_AUDIO_DETAILED_VIEW_H_
 
 #include "ash/system/tray/tray_details_view.h"
 #include "ash/system/tray/view_click_listener.h"
 #include "ash/system/user/login_status.h"
 #include "chromeos/audio/audio_device.h"
 
 #include "ui/gfx/font.h"
 
 namespace views {
 class View;
 }
 
 namespace ash {
 class HoverHighlightView;
 
 namespace tray {
 
 class AudioDetailedView : public TrayDetailsView,
                           public ViewClickListener {
  public:
   AudioDetailedView(SystemTrayItem* owner, user::LoginStatus login);
 
-  virtual ~AudioDetailedView();
+  ~AudioDetailedView() override;
 
   void Update();
 
  private:
   void AddScrollListInfoItem(const base::string16& text);
 
   HoverHighlightView* AddScrollListItem(const base::string16& text,
                                         gfx::Font::FontStyle style,
                                         bool checked);
 
   void CreateHeaderEntry();
   void CreateItems();
 
   void UpdateScrollableList();
   void UpdateAudioDevices();
 
   // Overridden from ViewClickListener.
-  virtual void OnViewClicked(views::View* sender) override;
+  void OnViewClicked(views::View* sender) override;
 
   user::LoginStatus login_;
 
   typedef std::map<views::View*, chromeos::AudioDevice> AudioDeviceMap;
 
   chromeos::AudioDeviceList output_devices_;
   chromeos::AudioDeviceList input_devices_;
   AudioDeviceMap device_map_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioDetailedView);
 };
 
 }  // namespace tray
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_CHROMEOS_AUDIO_AUDIO_DETAILED_VIEW_H_