Port flush_cache tool.

base/test_file_util.h

 // Copyright (c) 2008 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_TEST_FILE_UTIL_H_
 #define BASE_TEST_FILE_UTIL_H_
 
 // File utility functions used only by tests.
 
 #include <string>
 
+class FilePath;
+
 namespace file_util {
 
 // Clear a specific file from the system cache. After this call, trying
 // to access this file will result in a cold load from the hard drive.
-bool EvictFileFromSystemCache(const wchar_t* file);
+bool EvictFileFromSystemCache(const FilePath& file);
 
 // Like CopyFileNoCache but recursively copies all files and subdirectories
 // in the given input directory to the output directory. Any files in the
 // destination that already exist will be overwritten.
 //
 // Returns true on success. False means there was some error copying, so the
 // state of the destination is unknown.
 bool CopyRecursiveDirNoCache(const std::wstring& source_dir,
                              const std::wstring& dest_dir);
 
 }  // namespace file_util
 
 #endif  // BASE_TEST_FILE_UTIL_H_