Standardize usage of virtual/override/final in chrome/

chrome/common/extensions/chrome_manifest_url_handlers.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_COMMON_EXTENSIONS_CHROME_MANIFEST_URL_HANDLERS_H_
 #define CHROME_COMMON_EXTENSIONS_CHROME_MANIFEST_URL_HANDLERS_H_
 
 #include <string>
 
 #include "extensions/common/extension.h"
 #include "extensions/common/manifest_handler.h"
 
 // Chrome-specific extension manifest URL handlers.
 
 namespace base {
 class DictionaryValue;
 }
 
 namespace extensions {
 
 namespace chrome_manifest_urls {
 const GURL& GetDevToolsPage(const Extension* extension);
 }
 
 // Stores Chrome URL overrides specified in extensions manifests.
 struct URLOverrides : public Extension::ManifestData {
   typedef std::map<const std::string, GURL> URLOverrideMap;
 
   URLOverrides();
-  virtual ~URLOverrides();
+  ~URLOverrides() override;
 
   static const URLOverrideMap& GetChromeURLOverrides(
       const Extension* extension);
 
   // A map of chrome:// hostnames (newtab, downloads, etc.) to Extension URLs
   // which override the handling of those URLs. (see ExtensionOverrideUI).
   URLOverrideMap chrome_url_overrides_;
 };
 
 // Parses the "devtools_page" manifest key.
 class DevToolsPageHandler : public ManifestHandler {
  public:
   DevToolsPageHandler();
-  virtual ~DevToolsPageHandler();
+  ~DevToolsPageHandler() override;
 
-  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(DevToolsPageHandler);
 };
 
 // Parses the "chrome_url_overrides" manifest key.
 class URLOverridesHandler : public ManifestHandler {
  public:
   URLOverridesHandler();
-  virtual ~URLOverridesHandler();
+  ~URLOverridesHandler() override;
 
-  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(URLOverridesHandler);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_COMMON_EXTENSIONS_CHROME_MANIFEST_URL_HANDLERS_H_