Standardize usage of virtual/override/final in extensions/

extensions/common/manifest_handlers/shared_module_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_SHARED_MODULE_INFO_H_
 #define EXTENSIONS_COMMON_MANIFEST_HANDLERS_SHARED_MODULE_INFO_H_
 
 #include <string>
 #include <vector>
 
 #include "base/values.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/manifest_handler.h"
 
 namespace extensions {
 
 class SharedModuleInfo : public Extension::ManifestData {
  public:
   SharedModuleInfo();
-  virtual ~SharedModuleInfo();
+  ~SharedModuleInfo() override;
 
   bool Parse(const Extension* extension, base::string16* error);
 
   struct ImportInfo {
     std::string extension_id;
     std::string minimum_version;
   };
 
   // Utility functions.
   static void ParseImportedPath(const std::string& path,
@@ skipping 20 matching lines @@
   std::set<std::string> export_whitelist_;
 
   // Optional list of module imports of other extensions.
   std::vector<ImportInfo> imports_;
 };
 
 // Parses all import/export keys in the manifest.
 class SharedModuleHandler : public ManifestHandler {
  public:
   SharedModuleHandler();
-  virtual ~SharedModuleHandler();
+  ~SharedModuleHandler() 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;
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_MANIFEST_HANDLERS_SHARED_MODULE_INFO_H_