Escaping out of menu/autocomplete within a dialog causes the dialog to close

[willshowell]

Bug, feature request, or proposal:

Bug

Expected

Closing an autocomplete or menu from within a dialog via esc should only close the autocomplete panel / menu panel.

Current

Pressing esc closes the top dialog.

Reproduction

http://plnkr.co/edit/o9EQlYQKstYQdNsanheF?p=preview

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