allow for IE9+'s async focus, refs #11800
On IE9+ clicking a Button (with the mouse) to open a Dialog and then closing the Dialog doesn't refocus the Button, due to the async nature of the focus event.   But I don't think we should be guaranteeing refocus except when the Dialog was opened via keyboard (tabbing to the Button and then pressing ENTER/SPACE).   So changing the mouse test to not check for Dialog refocus.   Refs #16926.