Fix AOD2 notifications not waking up the device if the screen off animation played.

KeyguardViewMediator's isAnimatingScreenOff isn't always reset when going to sleep - it's sometimes only reset to false onStartedWakingUp. I'll fix that in a subsequent CL, but just in case that's a load-bearing bug, we'll do this first.

Fixes: 191231505
Test: tap notif on AOD2 after screen off plays
Change-Id: Ic13fbbaec9151ff577fc9914df1cbb9c42245ded