Revert of Add a parameter to FileStreamWriter::CreateForLocalFile to allow creating new

chrome/browser/chromeos/fileapi/file_system_backend.cc

 // Copyright 2013 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 "chrome/browser/chromeos/fileapi/file_system_backend.h"
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/stringprintf.h"
@@ skipping 292 matching lines @@
 
   if (url.type() == fileapi::kFileSystemTypeDrive)
     return drive_delegate_->CreateFileStreamWriter(url, offset, context);
 
   if (url.type() == fileapi::kFileSystemTypeRestrictedNativeLocal)
     return scoped_ptr<fileapi::FileStreamWriter>();
 
   DCHECK(url.type() == fileapi::kFileSystemTypeNativeLocal);
   return scoped_ptr<fileapi::FileStreamWriter>(
       fileapi::FileStreamWriter::CreateForLocalFile(
-          context->default_file_task_runner(), url.path(), offset,
-          fileapi::FileStreamWriter::OPEN_EXISTING_FILE));
+          context->default_file_task_runner(), url.path(), offset));
 }
 
 bool FileSystemBackend::GetVirtualPath(
     const base::FilePath& filesystem_path,
     base::FilePath* virtual_path) {
   return mount_points_->GetVirtualPath(filesystem_path, virtual_path) ||
          system_mount_points_->GetVirtualPath(filesystem_path, virtual_path);
 }
 
 }  // namespace chromeos