Standardize usage of virtual/override/final in chrome/

chrome/common/extensions/api/url_handlers/url_handlers_parser.h

 // Copyright 2013 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_COMMON_EXTENSIONS_API_URL_HANDLERS_URL_HANDLERS_PARSER_H_
 #define CHROME_COMMON_EXTENSIONS_API_URL_HANDLERS_URL_HANDLERS_PARSER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 12 matching lines @@
   // ID identifying this handler in the manifest.
   std::string id;
   // Handler title to display in all relevant UI.
   std::string title;
   // URL patterns associated with this handler.
   URLPatternSet patterns;
 };
 
 struct UrlHandlers : public Extension::ManifestData {
   UrlHandlers();
-  virtual ~UrlHandlers();
+  ~UrlHandlers() override;
 
   // Returns an array of URL handlers |extension| has defined in its manifest.
   static const std::vector<UrlHandlerInfo>* GetUrlHandlers(
       const Extension* extension);
 
   // Determines whether |extension| has at least one URL handler that matches
   // |url|.
   static bool CanExtensionHandleUrl(
       const Extension* extension,
       const GURL& url);
 
   // Finds a matching URL handler for |extension|, if any. Returns NULL in none
   // are found.
   static const UrlHandlerInfo* FindMatchingUrlHandler(
       const Extension* extension,
       const GURL& url);
 
   std::vector<UrlHandlerInfo> handlers;
 };
 
 // Parses the "url_handlers" manifest key.
 class UrlHandlersParser : public ManifestHandler {
  public:
   UrlHandlersParser();
-  virtual ~UrlHandlersParser();
+  ~UrlHandlersParser() override;
 
   // ManifestHandler API
-  virtual bool Parse(Extension* extension, base::string16* error) override;
+  bool Parse(Extension* extension, base::string16* error) override;
 
  private:
-  virtual const std::vector<std::string> Keys() const override;
+  const std::vector<std::string> Keys() const override;
 
   DISALLOW_COPY_AND_ASSIGN(UrlHandlersParser);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_COMMON_EXTENSIONS_API_URL_HANDLERS_URL_HANDLERS_PARSER_H_