Avoid flickering when unlocking with fingerprint

Fixes issue where scrim state could be set to KEYGUARD
for 1 frame and user would see the notification shade.

Change-Id: I577b969f98573fc481e3d7c283eb5b612b7e5cee
Fixes: 70210651
Test: Unlock with fingerprint from AoD
Test: runtest -x packages/SystemUI/tests/src/com/android/systemui/statusbar/phone/StatusBarTest.java