AX: Implement dismissrequest_dialog example https://rawgit.com/w3c/indie-ui/master/src/examples/dismissrequest_dialog/dismissrequest_dialog.html
<rdar://problem/20794828>
related to bug 144943
Looks like I filed this twice. Duping out to but 144065 aka <rdar://problem/20655266> *** This bug has been marked as a duplicate of bug 144065 ***