Make sure udfps bouncer always shows when requested

Even if the shade is expanding. This ensures that when the user
expands a notification that is hiding sensitive content,
that we still show the udfps bouncer even though the
transition to shade is also occuring (which normally hides the
udfps affordance).

Test: manual, atest UdfpsKeyguardViewControllerTest
Fixes: 197119617
Change-Id: Iac398a60ecf5137d0c3a8c77d700146e12fad0b7