Update {virtual,override} to follow C++11 style in chrome.

chrome/utility/shell_handler_win.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 CHROME_UTILITY_SHELL_HANDLER_WIN_H_
 #define CHROME_UTILITY_SHELL_HANDLER_WIN_H_
 
 #include <Windows.h>
 
 #include <vector>
@@ skipping 12 matching lines @@
     GetOpenFileNameFilter;
 
 struct ChromeUtilityMsg_GetSaveFileName_Params;
 
 // Handles requests to execute shell operations. Used to protect the browser
 // process from instability due to 3rd-party shell extensions. Must be invoked
 // in a non-sandboxed utility process.
 class ShellHandler : public UtilityMessageHandler {
  public:
   ShellHandler();
-  virtual ~ShellHandler();
+  ~ShellHandler() override;
 
   // IPC::Listener implementation
-  virtual bool OnMessageReceived(const IPC::Message& message) override;
+  bool OnMessageReceived(const IPC::Message& message) override;
 
  private:
   void OnOpenFileViaShell(const base::FilePath& full_path);
   void OnOpenFolderViaShell(const base::FilePath& full_path);
 
   void OnGetOpenFileName(
     HWND owner,
     DWORD flags,
     const GetOpenFileNameFilter& filter,
     const base::FilePath& initial_directory,
     const base::FilePath& filename);
 
   void OnGetSaveFileName(const ChromeUtilityMsg_GetSaveFileName_Params& params);
 
   DISALLOW_COPY_AND_ASSIGN(ShellHandler);
 };
 
 #endif  // CHROME_UTILITY_SHELL_HANDLER_WIN_H_