Remove #pragma once from chrome/browser/extensions

chrome/browser/extensions/crx_installer_error.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_CRX_INSTALLER_ERROR_H_
 #define CHROME_BROWSER_EXTENSIONS_CRX_INSTALLER_ERROR_H_
-#pragma once
 
 #include "base/string16.h"
 
 // Simple error class for CrxInstaller.
 class CrxInstallerError {
  public:
   // Typed errors that need to be handled specially by clients.
   enum Type {
     ERROR_NONE,
     ERROR_OFF_STORE,
@@ skipping 14 matching lines @@
 
   Type type() const { return type_; }
   const string16& message() const { return message_; }
 
  private:
   Type type_;
   string16 message_;
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_CRX_INSTALLER_ERROR_H_