Remove #pragma once. Just from base/ for now.

base/memory/scoped_handle.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 BASE_MEMORY_SCOPED_HANDLE_H_
 #define BASE_MEMORY_SCOPED_HANDLE_H_
-#pragma once
 
 #include <stdio.h>
 
 #include "base/basictypes.h"
 
 class ScopedStdioHandle {
  public:
   ScopedStdioHandle()
       : handle_(NULL) { }
 
@@ skipping 24 matching lines @@
     handle_ = newhandle;
   }
 
  private:
   FILE* handle_;
 
   DISALLOW_COPY_AND_ASSIGN(ScopedStdioHandle);
 };
 
 #endif  // BASE_MEMORY_SCOPED_HANDLE_H_