Refactor FileSystemMountPointProvider::CreateFileStream{Reader,Writer}

webkit/fileapi/file_system_context.h

Index: webkit/fileapi/file_system_context.h
diff --git a/webkit/fileapi/file_system_context.h b/webkit/fileapi/file_system_context.h
index 2286407ba3f9a5a8dbc5d180ac35e70a2428070f..0225a219ba320a311b780d4df1481d3e4ae64b4a 100644
--- a/webkit/fileapi/file_system_context.h
+++ b/webkit/fileapi/file_system_context.h
@@ -181,14 +181,14 @@ class WEBKIT_STORAGE_EXPORT FileSystemContext
   // MountPointProvider for the URL and call the provider's CreateFileReader.
   // The resolved MountPointProvider could perform further specialization
   // depending on the filesystem type pointed by the |url|.
-  webkit_blob::FileStreamReader* CreateFileStreamReader(
+  scoped_ptr<webkit_blob::FileStreamReader> CreateFileStreamReader(
       const FileSystemURL& url,
       int64 offset,
       const base::Time& expected_modification_time);
 
   // Creates new FileStreamWriter instance to write into a file pointed by
   // |url| from |offset|.
-  FileStreamWriter* CreateFileStreamWriter(
+  scoped_ptr<FileStreamWriter> CreateFileStreamWriter(
       const FileSystemURL& url,
       int64 offset);