Remove #pragma once from chrome/browser/extensions

chrome/browser/extensions/api/api_function.h

 // Copyright (c) 2012 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_API_API_FUNCTION_H_
 #define CHROME_BROWSER_EXTENSIONS_API_API_FUNCTION_H_
-#pragma once
 
 #include "chrome/browser/extensions/extension_function.h"
 #include "chrome/browser/extensions/api/api_resource.h"
 #include "content/public/browser/browser_thread.h"
 
 class ExtensionService;
 
 namespace extensions {
 
 class APIResourceController;
@@ skipping 54 matching lines @@
   // If you don't want your Work() method to happen on the IO thread, then set
   // this to the thread that you do want, preferably in Prepare().
   content::BrowserThread::ID work_thread_id_;
 
   ExtensionService* extension_service_;
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_API_FUNCTION_H_