Get rid of [Callback] extended attribute for parameters in IDL files

Source/modules/notifications/NotificationCenter.idl

Index: Source/modules/notifications/NotificationCenter.idl
diff --git a/Source/modules/notifications/NotificationCenter.idl b/Source/modules/notifications/NotificationCenter.idl
index 284659808e74140b2d98c09162ee6a5d43044f76..0263f91d52172279e0d694de9ce9b845952b7453 100644
--- a/Source/modules/notifications/NotificationCenter.idl
+++ b/Source/modules/notifications/NotificationCenter.idl
@@ -39,6 +39,6 @@
    [MeasureAs=LegacyTextNotifications, ActivityLog=Access, RaisesException] Notification createNotification(DOMString iconUrl, DOMString title, DOMString body);
 
    int checkPermission();
-   void requestPermission([Callback] optional VoidCallback callback);
+   void requestPermission(optional VoidCallback callback);
 };