Make MediaFileUtil run on thread pool.

webkit/fileapi/file_system_context.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.
 
 #ifndef WEBKIT_FILEAPI_FILE_SYSTEM_CONTEXT_H_
 #define WEBKIT_FILEAPI_FILE_SYSTEM_CONTEXT_H_
 
 #include <map>
 #include <string>
 
@@ skipping 40 matching lines @@
 class FILEAPI_EXPORT FileSystemContext
     : public base::RefCountedThreadSafe<FileSystemContext,
                                         DefaultContextDeleter> {
  public:
   // |file_task_runner| is used for all file operations and file related
   // meta operations.
   // The code assumes that file_task_runner->RunsTasksOnCurrentThread() returns
   // false if the current task is not running on the thread that allows
   // blocking file operations (like SequencedWorkerPool implementation does).
   FileSystemContext(
+      base::SequencedTaskRunner* media_task_runner,
       base::SequencedTaskRunner* file_task_runner,
       base::SingleThreadTaskRunner* io_task_runner,
       quota::SpecialStoragePolicy* special_storage_policy,
       quota::QuotaManagerProxy* quota_manager_proxy,
       const FilePath& profile_path,
       const FileSystemOptions& options);
 
   bool DeleteDataForOriginOnFileThread(const GURL& origin_url);
   bool DeleteDataForOriginAndTypeOnFileThread(const GURL& origin_url,
                                               FileSystemType type);
@@ skipping 98 matching lines @@
 
 struct DefaultContextDeleter {
   static void Destruct(const FileSystemContext* context) {
     context->DeleteOnCorrectThread();
   }
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_FILE_SYSTEM_CONTEXT_H_