Make MediaFileUtil run on thread pool.

webkit/fileapi/file_system_task_runners.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_TASK_RUNNERS_H_
+#define WEBKIT_FILEAPI_FILE_SYSTEM_TASK_RUNNERS_H_
+
+#include "base/memory/ref_counted.h"
+#include "webkit/fileapi/fileapi_export.h"
+
+namespace base {
+class SequencedTaskRunner;
+class SingleThreadTaskRunner;
+}  // namespace
+
+namespace fileapi {
+
+class FILEAPI_EXPORT FileSystemTaskRunners {
+ public:
+  FileSystemTaskRunners(
+      base::SingleThreadTaskRunner* io_task_runner,
+      base::SingleThreadTaskRunner* file_task_runner,
+      base::SequencedTaskRunner* media_task_runner);
+
+  FileSystemTaskRunners();

[kinuko, 2012/08/03 23:13:39]

Please add some comments, or add a static method like
CreateMockFileSystemTaskRunners() so that we can make sure we do not misuse this
class outside test code.  (I prefer the latter)

[tzik, 2012/08/04 00:24:21]

Done.

+
+  ~FileSystemTaskRunners();
+
+  base::SingleThreadTaskRunner* io_task_runner() {
+    return io_task_runner_.get();
+  }
+
+  base::SingleThreadTaskRunner* file_task_runner() {
+    return file_task_runner_.get();
+  }
+
+  base::SequencedTaskRunner* media_task_runner() {
+    return media_task_runner_.get();
+  }
+
+ private:
+  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
+  scoped_refptr<base::SingleThreadTaskRunner> file_task_runner_;
+

[kinuko, 2012/08/03 23:13:39]

nit: please remove this empty line

[tzik, 2012/08/04 00:24:21]

Done.

+  scoped_refptr<base::SequencedTaskRunner> media_task_runner_;
+
+  DISALLOW_COPY_AND_ASSIGN(FileSystemTaskRunners);
+};
+
+}  // namespace fileapi
+
+#endif  // WEBKIT_FILEAPI_FILE_SYSTEM_TASK_RUNNERS_H_