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

chrome/browser/browsing_data/mock_browsing_data_flash_lso_helper.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 CHROME_BROWSER_BROWSING_DATA_MOCK_BROWSING_DATA_FLASH_LSO_HELPER_H_
 #define CHROME_BROWSER_BROWSING_DATA_MOCK_BROWSING_DATA_FLASH_LSO_HELPER_H_
 
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "chrome/browser/browsing_data/browsing_data_flash_lso_helper.h"
 
 class MockBrowsingDataFlashLSOHelper : public BrowsingDataFlashLSOHelper {
  public:
   explicit MockBrowsingDataFlashLSOHelper(
       content::BrowserContext* browser_context);
 
   // BrowsingDataFlashLSOHelper implementation:
-  virtual void StartFetching(
-      const GetSitesWithFlashDataCallback& callback) override;
-  virtual void DeleteFlashLSOsForSite(const std::string& site) override;
+  void StartFetching(const GetSitesWithFlashDataCallback& callback) override;
+  void DeleteFlashLSOsForSite(const std::string& site) override;
 
   // Adds a domain sample.
   void AddFlashLSODomain(const std::string& domain);
 
   // Notifies the callback.
   void Notify();
 
   // Returns true if the domain list is empty.
   bool AllDeleted();
 
  private:
-  virtual ~MockBrowsingDataFlashLSOHelper();
+  ~MockBrowsingDataFlashLSOHelper() override;
 
   GetSitesWithFlashDataCallback callback_;
 
   std::vector<std::string> domains_;
 
   DISALLOW_COPY_AND_ASSIGN(MockBrowsingDataFlashLSOHelper);
 };
 
 #endif  // CHROME_BROWSER_BROWSING_DATA_MOCK_BROWSING_DATA_FLASH_LSO_HELPER_H_