Cleanup: Remove remaining deprecated file_util functions.

base/file_util_deprecated.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.
-
-// We're trying to transition away from paths as wstrings into using
-// FilePath objects.  This file contains declarations of deprecated
-// functions.  By hiding them here rather in the main header, we hope
-// to discourage callers.
-
-// See file_util.h for documentation on all functions that don't have
-// documentation here.
-
-#ifndef BASE_FILE_UTIL_DEPRECATED_H_
-#define BASE_FILE_UTIL_DEPRECATED_H_
-#pragma once
-
-#include "base/base_export.h"
-#include "build/build_config.h"
-
-// We've successfully deprecated all of these functions on non-Windows
-// platforms.
-
-#if !defined(OS_WIN)
-#error Do not include on non-Windows platforms.
-#endif
-
-namespace file_util {
-
-// Use the FilePath versions instead.
-BASE_EXPORT FILE* OpenFile(const std::string& filename, const char* mode);
-BASE_EXPORT FILE* OpenFile(const std::wstring& filename, const char* mode);
-
-// Use version that takes a FilePath.
-BASE_EXPORT int ReadFile(const std::wstring& filename, char* data, int size);
-BASE_EXPORT int WriteFile(const std::wstring& filename,
-                          const char* data, int size);
-
-}  // namespace file_util
-
-#endif  // BASE_FILE_UTIL_DEPRECATED_H_