Remove #pragma once from chrome/browser/extensions

chrome/browser/extensions/extension_message_handler.h

 // Copyright (c) 2011 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_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_HANDLER_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_HANDLER_H_
-#pragma once
 
 #include <string>
 
 #include "content/public/browser/render_view_host_observer.h"
 
 // Filters and dispatches extension-related IPC messages that arrive from
 // renderers. There is one of these objects for each RenderViewHost in Chrome.
 // Contrast this with ExtensionTabHelper, which is only created for WebContents.
 //
 // TODO(aa): Handling of content script messaging should be able to move to EFD
@@ skipping 12 matching lines @@
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 
  private:
   // Message handlers.
   void OnPostMessage(int port_id, const std::string& message);
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionMessageHandler);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_HANDLER_H_