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

chrome/browser/browsing_data/mock_browsing_data_file_system_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_FILE_SYSTEM_HELPER_H_
 #define CHROME_BROWSER_BROWSING_DATA_MOCK_BROWSING_DATA_FILE_SYSTEM_HELPER_H_
 
 #include <list>
 #include <map>
 #include <string>
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "chrome/browser/browsing_data/browsing_data_file_system_helper.h"
 
 // Mock for BrowsingDataFileSystemHelper.
 // Use AddFileSystemSamples() or add directly to response_ list, then call
 // Notify().
 class MockBrowsingDataFileSystemHelper : public BrowsingDataFileSystemHelper {
  public:
   explicit MockBrowsingDataFileSystemHelper(Profile* profile);
 
   // BrowsingDataFileSystemHelper implementation.
-  virtual void StartFetching(const base::Callback<
-      void(const std::list<FileSystemInfo>&)>& callback) override;
-  virtual void DeleteFileSystemOrigin(const GURL& origin) override;
+  void StartFetching(
+      const base::Callback<void(const std::list<FileSystemInfo>&)>& callback)
+      override;
+  void DeleteFileSystemOrigin(const GURL& origin) override;
 
   // Adds a specific filesystem.
   void AddFileSystem(const GURL& origin,
                      bool has_persistent,
                      bool has_temporary,
                      bool has_syncable);
 
   // Adds some FilesystemInfo samples.
   void AddFileSystemSamples();
 
   // Notifies the callback.
   void Notify();
 
   // Marks all filesystems as existing.
   void Reset();
 
   // Returns true if all filesystemss since the last Reset() invocation were
   // deleted.
   bool AllDeleted();
 
   GURL last_deleted_origin_;
 
  private:
-  virtual ~MockBrowsingDataFileSystemHelper();
+  ~MockBrowsingDataFileSystemHelper() override;
 
   base::Callback<void(const std::list<FileSystemInfo>&)> callback_;
 
   // Stores which filesystems exist.
   std::map<const std::string, bool> file_systems_;
 
   std::list<FileSystemInfo> response_;
 
   DISALLOW_COPY_AND_ASSIGN(MockBrowsingDataFileSystemHelper);
 };
 
 #endif  // CHROME_BROWSER_BROWSING_DATA_MOCK_BROWSING_DATA_FILE_SYSTEM_HELPER_H_