Standardize usage of virtual/override/final specifiers.

ash/system/locale/locale_notification_controller.cc

Index: ash/system/locale/locale_notification_controller.cc
diff --git a/ash/system/locale/locale_notification_controller.cc b/ash/system/locale/locale_notification_controller.cc
index 656ddb4cc1497dac092712bc9457e871a2b2bf01..63a4210591d4c872f84c340ee91e44c3ae9bcc38 100644
--- a/ash/system/locale/locale_notification_controller.cc
+++ b/ash/system/locale/locale_notification_controller.cc
@@ -29,15 +29,15 @@ class LocaleNotificationDelegate : public message_center::NotificationDelegate {
   explicit LocaleNotificationDelegate(LocaleObserver::Delegate* delegate);
 
  protected:
-  virtual ~LocaleNotificationDelegate();
+  ~LocaleNotificationDelegate() override;
 
   // message_center::NotificationDelegate overrides:
-  virtual void Display() override;
-  virtual void Error() override;
-  virtual void Close(bool by_user) override;
-  virtual bool HasClickedListener() override;
-  virtual void Click() override;
-  virtual void ButtonClick(int button_index) override;
+  void Display() override;
+  void Error() override;
+  void Close(bool by_user) override;
+  bool HasClickedListener() override;
+  void Click() override;
+  void ButtonClick(int button_index) override;
 
  private:
   LocaleObserver::Delegate* delegate_;