Dismiss Permission Grant dialog when Rational dialog is dismissed

Tapping outside the permission rationale dialog should also dismiss the
grant dialog behind it, if the rationale dialog is not triggered from
settings.

Also removes an unneeded setting of the dim amount

Fixes: 272510355
Test: manual
Change-Id: Ic4867f2534b6a1091da0a1c47954f1cce57577e4