Create ShareableFileReference on IO thread

webkit/fileapi/local_file_util.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_LOCAL_FILE_UTIL_H_
 #define WEBKIT_FILEAPI_LOCAL_FILE_UTIL_H_
 
 #include <vector>
 
 #include "base/callback_forward.h"
@@ skipping 85 matching lines @@
   virtual PlatformFileError CopyInForeignFile(
         FileSystemOperationContext* context,
         const FilePath& src_file_path,
         const FileSystemURL& dest_url) OVERRIDE;
   virtual PlatformFileError DeleteFile(
       FileSystemOperationContext* context,
       const FileSystemURL& url) OVERRIDE;
   virtual PlatformFileError DeleteSingleDirectory(
       FileSystemOperationContext* context,
       const FileSystemURL& url) OVERRIDE;
-  virtual scoped_refptr<webkit_blob::ShareableFileReference>
-      CreateSnapshotFile(FileSystemOperationContext* context,
-                         const FileSystemURL& url,
-                         base::PlatformFileError* result,
-                         base::PlatformFileInfo* file_info,
-                         FilePath* platform_path) OVERRIDE;
+  virtual PlatformFileError CreateSnapshotFile(
+      FileSystemOperationContext* context,
+      const FileSystemURL& url,
+      base::PlatformFileInfo* file_info,
+      FilePath* platform_path,
+      SnapshotFilePolicy* snapshot_policy) OVERRIDE;
 
  private:
   // Given the filesystem url, produces a real, full local path for the
   // underlying filesystem (which is usually the native filesystem).
   FileSystemURL GetLocalPath(
       FileSystemOperationContext* context,
       const FileSystemURL& url);
 
   DISALLOW_COPY_AND_ASSIGN(LocalFileUtil);
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_LOCAL_FILE_UTIL_H_