IndexedDB: Fixed support for empty blobs.

storage/browser/fileapi/isolated_file_system_backend.cc

 // 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.
 
 #include "storage/browser/fileapi/isolated_file_system_backend.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
@@ skipping 122 matching lines @@
           context->default_file_task_runner(),
           url.path(),
           offset,
           expected_modification_time));
 }
 
 scoped_ptr<FileStreamWriter> IsolatedFileSystemBackend::CreateFileStreamWriter(
     const FileSystemURL& url,
     int64 offset,
     FileSystemContext* context) const {
-  return scoped_ptr<FileStreamWriter>(
-      FileStreamWriter::CreateForLocalFile(
-          context->default_file_task_runner(),
-          url.path(),
-          offset,
-          FileStreamWriter::OPEN_EXISTING_FILE));
+  return scoped_ptr<FileStreamWriter>(FileStreamWriter::CreateForLocalFile(
+      context->default_file_task_runner(), url.path(), offset));
 }
 
 FileSystemQuotaUtil* IsolatedFileSystemBackend::GetQuotaUtil() {
   // No quota support.
   return NULL;
 }
 
 const UpdateObserverList* IsolatedFileSystemBackend::GetUpdateObservers(
     FileSystemType type) const {
   return NULL;
 }
 
 const ChangeObserverList* IsolatedFileSystemBackend::GetChangeObservers(
     FileSystemType type) const {
   return NULL;
 }
 
 const AccessObserverList* IsolatedFileSystemBackend::GetAccessObservers(
     FileSystemType type) const {
   return NULL;
 }
 
 }  // namespace storage