replace OVERRIDE and FINAL with override and final in ash/

ash/system/chromeos/audio/tray_audio_chromeos.h

Index: ash/system/chromeos/audio/tray_audio_chromeos.h
diff --git a/ash/system/chromeos/audio/tray_audio_chromeos.h b/ash/system/chromeos/audio/tray_audio_chromeos.h
index c5cb9eaaf3ae1444f3d99025a35ce38fad1115fd..a41ce503f72166663cb506d929638274fb8d66a1 100644
--- a/ash/system/chromeos/audio/tray_audio_chromeos.h
+++ b/ash/system/chromeos/audio/tray_audio_chromeos.h
@@ -21,12 +21,12 @@ class ASH_EXPORT TrayAudioChromeOs : public TrayAudio {
 
  protected:
   // Overridden from TrayAudio
-  virtual void Update() OVERRIDE;
+  virtual void Update() override;
 
  private:
   // Overridden from SystemTrayItem.
-  virtual views::View* CreateDetailedView(user::LoginStatus status) OVERRIDE;
-  virtual void DestroyDetailedView() OVERRIDE;
+  virtual views::View* CreateDetailedView(user::LoginStatus status) override;
+  virtual void DestroyDetailedView() override;
 
   tray::AudioDetailedView* audio_detail_view_;