Standardize usage of virtual/override/final in chrome/browser/

chrome/browser/renderer_context_menu/context_menu_content_type_extension_popup.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 CHROME_BROWSER_RENDERER_CONTEXT_MENU_CONTEXT_MENU_CONTENT_TYPE_EXTENSION_POPUP_H_
 #define CHROME_BROWSER_RENDERER_CONTEXT_MENU_CONTEXT_MENU_CONTENT_TYPE_EXTENSION_POPUP_H_
 
 #include "components/renderer_context_menu/context_menu_content_type.h"
 
 class ContextMenuContentTypeExtensionPopup : public ContextMenuContentType {
  public:
-  virtual ~ContextMenuContentTypeExtensionPopup();
+  ~ContextMenuContentTypeExtensionPopup() override;
 
   // ContextMenuContentType overrides.
-  virtual bool SupportsGroup(int group) override;
+  bool SupportsGroup(int group) override;
 
  protected:
   ContextMenuContentTypeExtensionPopup(
       content::WebContents* web_contents,
       const content::ContextMenuParams& params);
 
  private:
   friend class ContextMenuContentTypeFactory;
 
   DISALLOW_COPY_AND_ASSIGN(ContextMenuContentTypeExtensionPopup);
 };
 
 #endif  // CHROME_BROWSER_RENDERER_CONTEXT_MENU_CONTEXT_MENU_CONTENT_TYPE_EXTENSION_POPUP_H_