WakeAndUnlock: Make sure blanking is never animated

Fixes an issue where instead of immediately blanking the screen upon
authenticating via fingerprint we animated to blank because another
animating transition was requested at the same time.

Change-Id: I141079c0d4de1776c8328057d364eeb0964eebaf
Fixes: 64080116
Test: Unlock via fingerprint a lot. Verify no flicker.
(cherry picked from commit e06956e5)