Create ShareableFileReference on IO thread

webkit/fileapi/obfuscated_file_util.h

Index: webkit/fileapi/obfuscated_file_util.h
diff --git a/webkit/fileapi/obfuscated_file_util.h b/webkit/fileapi/obfuscated_file_util.h
index 57f280f8097725775cd850d5a4c025583a40ee00..51b2c475e0188dca764f741e25c7af83d0eeaba4 100644
--- a/webkit/fileapi/obfuscated_file_util.h
+++ b/webkit/fileapi/obfuscated_file_util.h
@@ -122,12 +122,12 @@ class FILEAPI_EXPORT_PRIVATE ObfuscatedFileUtil : public FileSystemFileUtil {
   virtual base::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 base::PlatformFileError CreateSnapshotFile(
+      FileSystemOperationContext* context,
+      const FileSystemURL& url,
+      base::PlatformFileInfo* file_info,
+      FilePath* platform_path,
+      SnapshotFilePolicy* policy) OVERRIDE;
 
   // Gets the topmost directory specific to this origin and type.  This will
   // contain both the directory database's files and all the backing file