Make MediaFileUtil run on thread pool.

webkit/fileapi/isolated_mount_point_provider.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_ISOLATED_MOUNT_POINT_PROVIDER_H_
 #define WEBKIT_FILEAPI_ISOLATED_MOUNT_POINT_PROVIDER_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/ref_counted.h"
 #include "webkit/fileapi/file_system_mount_point_provider.h"
 
+namespace base {
+class SequencedTaskRunner;
+}
+
 namespace fileapi {
 
 class DraggedFileUtil;
 class IsolatedContext;
 class IsolatedFileUtil;
 class MediaPathFilter;
 class NativeMediaFileUtil;
 
 class IsolatedMountPointProvider : public FileSystemMountPointProvider {
  public:
   typedef FileSystemMountPointProvider::ValidateFileSystemCallback
       ValidateFileSystemCallback;
 
-  IsolatedMountPointProvider();
+  explicit IsolatedMountPointProvider(
+      base::SequencedTaskRunner* media_task_runner);
   virtual ~IsolatedMountPointProvider();
 
   // FileSystemMountPointProvider implementation.
   virtual void ValidateFileSystemRoot(
       const GURL& origin_url,
       FileSystemType type,
       bool create,
       const ValidateFileSystemCallback& callback) OVERRIDE;
   virtual FilePath GetFileSystemRootPathOnFileThread(
       const GURL& origin_url,
@@ skipping 16 matching lines @@
     FileSystemContext* context) const OVERRIDE;
   virtual FileStreamWriter* CreateFileStreamWriter(
     const FileSystemURL& url,
     int64 offset,
     FileSystemContext* context) const OVERRIDE;
   virtual FileSystemQuotaUtil* GetQuotaUtil() OVERRIDE;
 
  private:
   scoped_ptr<MediaPathFilter> media_path_filter_;
 
+  scoped_refptr<base::SequencedTaskRunner> media_task_runner_;
+
   scoped_ptr<IsolatedFileUtil> isolated_file_util_;
   scoped_ptr<DraggedFileUtil> dragged_file_util_;
   scoped_ptr<NativeMediaFileUtil> native_media_file_util_;
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_ISOLATED_MOUNT_POINT_PROVIDER_H_