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

chrome/browser/extensions/api/file_system/entry_watcher_service_factory.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_EXTENSIONS_API_FILE_SYSTEM_ENTRY_WATCHER_SERVICE_FACTORY_H_
 #define CHROME_BROWSER_EXTENSIONS_API_FILE_SYSTEM_ENTRY_WATCHER_SERVICE_FACTORY_H_
 
 #include "base/memory/singleton.h"
 #include "components/keyed_service/content/browser_context_keyed_service_factory.h"
 
@@ skipping 16 matching lines @@
   // NULL.
   static EntryWatcherService* FindExisting(content::BrowserContext* context);
 
   // Gets a singleton instance of the factory.
   static EntryWatcherServiceFactory* GetInstance();
 
  private:
   friend struct DefaultSingletonTraits<EntryWatcherServiceFactory>;
 
   EntryWatcherServiceFactory();
-  virtual ~EntryWatcherServiceFactory();
+  ~EntryWatcherServiceFactory() override;
 
   // BrowserContextKeyedServiceFactory overrides:
-  virtual KeyedService* BuildServiceInstanceFor(
+  KeyedService* BuildServiceInstanceFor(
       content::BrowserContext* profile) const override;
-  virtual bool ServiceIsCreatedWithBrowserContext() const override;
+  bool ServiceIsCreatedWithBrowserContext() const override;
 
   DISALLOW_COPY_AND_ASSIGN(EntryWatcherServiceFactory);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_FILE_SYSTEM_ENTRY_WATCHER_SERVICE_FACTORY_H_