Now it is necessary to actually press the exact "OK" or Back button to
get the dialog to dismiss. This makes pocket wiping that little bit less
likely.
Bug: 32934848
Test: manual, enter the password too many times. The dialog should appear. Attempt to dismiss it by tapping outside the dialog. This should not happen.
Test: correctness of .setCanceledOnTouchOutside is outside scope.
Change-Id: Icff8bd9068f636c0a75decb787b8a5c9161a8cbd
11bf78028e