Standardize usage of virtual/override/final specifiers.

ash/shelf/app_list_button.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_SHELF_APP_LIST_BUTTON_H_
 #define ASH_SHELF_APP_LIST_BUTTON_H_
 
 #include "ui/views/controls/button/image_button.h"
 
 namespace ash {
 class ShelfButtonHost;
 class ShelfWidget;
 
 // Button used for the AppList icon on the shelf.
 class AppListButton : public views::ImageButton {
  public:
   // Bounds size (inset) required for the app icon image (in pixels).
   static const int kImageBoundsSize;
 
   AppListButton(views::ButtonListener* listener,
                 ShelfButtonHost* host,
                 ShelfWidget* shelf_widget);
-  virtual ~AppListButton();
+  ~AppListButton() override;
 
   bool draw_background_as_active() {
     return draw_background_as_active_;
   }
 
  protected:
   // views::ImageButton overrides:
-  virtual bool OnMousePressed(const ui::MouseEvent& event) override;
-  virtual void OnMouseReleased(const ui::MouseEvent& event) override;
-  virtual void OnMouseCaptureLost() override;
-  virtual bool OnMouseDragged(const ui::MouseEvent& event) override;
-  virtual void OnMouseMoved(const ui::MouseEvent& event) override;
-  virtual void OnMouseEntered(const ui::MouseEvent& event) override;
-  virtual void OnMouseExited(const ui::MouseEvent& event) override;
-  virtual void OnPaint(gfx::Canvas* canvas) override;
-  virtual void GetAccessibleState(ui::AXViewState* state) override;
+  bool OnMousePressed(const ui::MouseEvent& event) override;
+  void OnMouseReleased(const ui::MouseEvent& event) override;
+  void OnMouseCaptureLost() override;
+  bool OnMouseDragged(const ui::MouseEvent& event) override;
+  void OnMouseMoved(const ui::MouseEvent& event) override;
+  void OnMouseEntered(const ui::MouseEvent& event) override;
+  void OnMouseExited(const ui::MouseEvent& event) override;
+  void OnPaint(gfx::Canvas* canvas) override;
+  void GetAccessibleState(ui::AXViewState* state) override;
 
   // ui::EventHandler overrides:
-  virtual void OnGestureEvent(ui::GestureEvent* event) override;
+  void OnGestureEvent(ui::GestureEvent* event) override;
 
  private:
   // Toggles the active state for painting the background and schedules a paint.
   void SetDrawBackgroundAsActive(bool draw_background_as_active);
 
   // True if the background should render as active, regardless of the state of
   // the application list.
   bool draw_background_as_active_;
 
   ShelfButtonHost* host_;
   // Reference to the shelf widget containing this button, owned by the
   // root window controller.
   ShelfWidget* shelf_widget_;
 
   DISALLOW_COPY_AND_ASSIGN(AppListButton);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELF_APP_LIST_BUTTON_H_