Standardize usage of virtual/override/final in extensions/

extensions/common/manifest_handlers/kiosk_mode_info.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 EXTENSIONS_COMMON_MANIFEST_HANDLERS_KIOSK_MODE_INFO_H_
 #define EXTENSIONS_COMMON_MANIFEST_HANDLERS_KIOSK_MODE_INFO_H_
 
 #include <string>
 #include <vector>
 
 #include "extensions/common/extension.h"
 #include "extensions/common/manifest.h"
 #include "extensions/common/manifest_handler.h"
 
 namespace extensions {
 
 struct KioskModeInfo : public Extension::ManifestData {
  public:
   enum KioskStatus {
     NONE,
     ENABLED,
     ONLY
   };
 
   explicit KioskModeInfo(KioskStatus kiosk_status);
-  virtual ~KioskModeInfo();
+  ~KioskModeInfo() override;
 
   KioskStatus kiosk_status;
 
   // Whether the extension or app is enabled for app kiosk mode.
   static bool IsKioskEnabled(const Extension* extension);
 
   // Whether the extension or app should only be available in kiosk mode.
   static bool IsKioskOnly(const Extension* extension);
 };
 
 // Parses the "kiosk_enabled" and "kiosk_only" manifest keys.
 class KioskModeHandler : public ManifestHandler {
  public:
   KioskModeHandler();
-  virtual ~KioskModeHandler();
+  ~KioskModeHandler() 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;
 
   std::vector<std::string> supported_keys_;
 
   DISALLOW_COPY_AND_ASSIGN(KioskModeHandler);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_MANIFEST_HANDLERS_KIOSK_MODE_INFO_H_