Standardize usage of virtual/override/final in extensions/

extensions/browser/guest_view/web_view/web_view_permission_helper_delegate.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 EXTENSIONS_BROWSER_GUEST_VIEW_WEB_VIEW_WEB_VIWE_PERMISSION_HELPER_DELEGATE_H_
 #define EXTENSIONS_BROWSER_GUEST_VIEW_WEB_VIEW_WEB_VIWE_PERMISSION_HELPER_DELEGATE_H_
 
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/common/media_stream_request.h"
 #include "extensions/browser/guest_view/web_view/web_view_permission_helper.h"
 
 namespace extensions {
 
 // A delegate class of WebViewPermissionHelper to request permissions that are
 // not a part of extensions.
 class WebViewPermissionHelperDelegate : public content::WebContentsObserver {
  public:
   explicit WebViewPermissionHelperDelegate(
       WebViewPermissionHelper* web_view_permission_helper);
-  virtual ~WebViewPermissionHelperDelegate();
+  ~WebViewPermissionHelperDelegate() override;
 
   virtual void CanDownload(
       content::RenderViewHost* render_view_host,
       const GURL& url,
       const std::string& request_method,
       const base::Callback<void(bool)>& callback) {}
 
   virtual void RequestPointerLockPermission(
       bool user_gesture,
       bool last_unlocked_by_target,
@@ skipping 54 matching lines @@
 
  private:
   WebViewPermissionHelper* const web_view_permission_helper_;
 
   DISALLOW_COPY_AND_ASSIGN(WebViewPermissionHelperDelegate);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_GUEST_VIEW_WEB_VIEW_WEB_VIWE_PERMISSION_HELPER_DELEGATE_H_