Change FileStream to use FilePath instead of wstring.

net/url_request/url_request_file_job.cc

 // Copyright (c) 2006-2008 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.
 
 // For loading files, we make use of overlapped i/o to ensure that reading from
 // the filesystem (e.g., a network filesystem) does not block the calling
 // thread.  An alternative approach would be to use a background thread or pool
 // of threads, but it seems better to leverage the operating system's ability
 // to do background file reads for us.
 //
@@ skipping 154 matching lines @@
     return;
 
   int rv = net::OK;
   if (!exists) {
     rv = net::ERR_FILE_NOT_FOUND;
   } else {
     DCHECK(!file_info.is_directory);
     int flags = base::PLATFORM_FILE_OPEN |
                 base::PLATFORM_FILE_READ |
                 base::PLATFORM_FILE_ASYNC;
-    rv = stream_.Open(file_path_.ToWStringHack(), flags);
+    rv = stream_.Open(file_path_, flags);
   }
 
   if (rv == net::OK) {
     set_expected_content_size(file_info.size);
     NotifyHeadersComplete();
   } else {
     NotifyDone(URLRequestStatus(URLRequestStatus::FAILED, rv));
   }
 }
 
@@ skipping 28 matching lines @@
     return false;
 
   *location = net::FilePathToFileURL(new_path);
   *http_status_code = 301;
   return true;
 #else
   return false;
 #endif
 }