Remove #pragma once from chrome/browser/extensions

chrome/browser/extensions/api/identity/web_auth_flow.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_IDENTITY_WEB_AUTH_FLOW_H_
 #define CHROME_BROWSER_EXTENSIONS_API_IDENTITY_WEB_AUTH_FLOW_H_
-#pragma once
 
 #include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "chrome/browser/ui/extensions/web_auth_flow_window.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "googleurl/src/gurl.h"
 
@@ skipping 91 matching lines @@
 
   content::WebContents* contents_;
   WebAuthFlowWindow* window_;
 
   DISALLOW_COPY_AND_ASSIGN(WebAuthFlow);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_IDENTITY_WEB_AUTH_FLOW_H_