Port base/files/file_util_proxy to Native Client.

base/platform_file.cc

 // 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.
 
 #include "base/platform_file.h"
 
 namespace base {
 
 PlatformFileInfo::PlatformFileInfo()
     : size(0),
       is_directory(false),
       is_symbolic_link(false) {
 }
 
 PlatformFileInfo::~PlatformFileInfo() {}
 
+#if !defined(OS_NACL)
 PlatformFile CreatePlatformFile(const FilePath& name,
                                 int flags,
                                 bool* created,
                                 PlatformFileError* error) {
   if (name.ReferencesParent()) {
     if (error)
       *error = PLATFORM_FILE_ERROR_ACCESS_DENIED;
     return kInvalidPlatformFileValue;
   }
   return CreatePlatformFileUnsafe(name, flags, created, error);
 }
+#endif
 
 }  // namespace base