Standardize usage of virtual/override/final specifiers.

ash/shell/context_menu.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 ASH_SHELL_CONTEXT_MENU_H_
 #define ASH_SHELL_CONTEXT_MENU_H_
 
 #include "ash/shelf/shelf_alignment_menu.h"
 #include "ash/shelf/shelf_types.h"
 #include "base/basictypes.h"
 #include "ui/base/models/simple_menu_model.h"
 
 namespace aura {
 class RootWindow;
 }
 
 namespace ash {
 namespace shell {
 
 // Context menu for the ash_shell.
 class ContextMenu : public ui::SimpleMenuModel,
                     public ui::SimpleMenuModel::Delegate {
  public:
   explicit ContextMenu(aura::Window* root);
-  virtual ~ContextMenu();
+  ~ContextMenu() override;
 
   // ui::SimpleMenuModel::Delegate overrides:
-  virtual bool IsCommandIdChecked(int command_id) const override;
-  virtual bool IsCommandIdEnabled(int command_id) const override;
-  virtual bool GetAcceleratorForCommandId(
-      int command_id,
-      ui::Accelerator* accelerator) override;
-  virtual void ExecuteCommand(int command_id, int event_flags) override;
+  bool IsCommandIdChecked(int command_id) const override;
+  bool IsCommandIdEnabled(int command_id) const override;
+  bool GetAcceleratorForCommandId(int command_id,
+                                  ui::Accelerator* accelerator) override;
+  void ExecuteCommand(int command_id, int event_flags) override;
 
  private:
   enum MenuItem {
     MENU_AUTO_HIDE,
     MENU_ALIGNMENT_MENU,
   };
 
   aura::Window* root_window_;
 
   ShelfAlignmentMenu alignment_menu_;
 
   DISALLOW_COPY_AND_ASSIGN(ContextMenu);
 };
 
 }  // namespace shell
 }  // namespace ash
 
 #endif  // ASH_SHELL_CONTEXT_MENU_H_