[macosx] No way to hide(), dispose() FileDialog

Run for instance closed/java/awt/Dialog/FileDialogTest/FileDialogTest. There, on a button press, a FileDialog is created and a Thread is started which calls hide() or dispose() on this FileDialog, after a delay. FileDialog is shown immediately after that.

Now, no hide() nor dispose() has any effect. There seems to be no way to remove FileDialog other than user's action.

It's not a regression though. 7u4 and Apple Java behave just the same way.