Standardize usage of virtual/override/final in extensions/

extensions/common/manifest_handlers/options_page_info.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 EXTENSIONS_COMMON_MANIFEST_HANDLERS_OPTIONS_PAGE_INFO_H_
 #define EXTENSIONS_COMMON_MANIFEST_HANDLERS_OPTIONS_PAGE_INFO_H_
 
 #include <string>
 #include <vector>
 
 #include "base/values.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/manifest_handler.h"
 #include "url/gurl.h"
 
 namespace base {
 class Value;
 }
 
 namespace extensions {
 
 // A class to provide options page configuration settings from the manifest.
 class OptionsPageInfo : public Extension::ManifestData {
  public:
   OptionsPageInfo(const GURL& options_page,
                   bool chrome_styles,
                   bool open_in_tab);
-  virtual ~OptionsPageInfo();
+  ~OptionsPageInfo() override;
 
   // Returns the URL to the given extension's options page. This method supports
   // both the "options_ui.page" field and the legacy "options_page" field. If
   // both are present, it will return the value of "options_ui.page".
   static const GURL& GetOptionsPage(const Extension* extension);
 
   // Returns true if the given extension has an options page. An extension has
   // an options page if one or both of "options_ui.page" and "options_page"
   // specify a valid options page.
   static bool HasOptionsPage(const Extension* extension);
@@ skipping 23 matching lines @@
 
   bool open_in_tab_;
 
   DISALLOW_COPY_AND_ASSIGN(OptionsPageInfo);
 };
 
 // Parses the "options_ui" manifest key and the legacy "options_page" key.
 class OptionsPageManifestHandler : public ManifestHandler {
  public:
   OptionsPageManifestHandler();
-  virtual ~OptionsPageManifestHandler();
+  ~OptionsPageManifestHandler() override;
 
-  virtual bool Parse(Extension* extension, base::string16* error) override;
-  virtual bool Validate(const Extension* extension,
-                        std::string* error,
-                        std::vector<InstallWarning>* warnings) const override;
+  bool Parse(Extension* extension, base::string16* error) override;
+  bool Validate(const Extension* extension,
+                std::string* error,
+                std::vector<InstallWarning>* warnings) const override;
 
  private:
-  virtual const std::vector<std::string> Keys() const override;
+  const std::vector<std::string> Keys() const override;
 
   DISALLOW_COPY_AND_ASSIGN(OptionsPageManifestHandler);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_MANIFEST_HANDLERS_OPTIONS_PAGE_INFO_H_