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

base/process_util.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.
 
 // This file/namespace contains utility functions for enumerating, ending and
 // computing statistics of processes.
 
 #ifndef BASE_PROCESS_UTIL_H_
 #define BASE_PROCESS_UTIL_H_
-#pragma once
 
 #include "base/basictypes.h"
 #include "base/time.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
 #include <tlhelp32.h>
 #elif defined(OS_MACOSX) || defined(OS_BSD)
 // kinfo_proc is defined in <sys/sysctl.h>, but this forward declaration
 // is sufficient for the vector<kinfo_proc> below.
@@ skipping 833 matching lines @@
 // instance running inside the parent.  The parent's Breakpad instance should
 // not handle the child's exceptions.  Calling RestoreDefaultExceptionHandler
 // in the child after forking will restore the standard exception handler.
 // See http://crbug.com/20371/ for more details.
 void RestoreDefaultExceptionHandler();
 #endif  // defined(OS_MACOSX)
 
 }  // namespace base
 
 #endif  // BASE_PROCESS_UTIL_H_