Fix opacity of expanded shade during transitions

Change-Id: I2dba88ea52b58d12fc2a858639d270b41403a22c
Fixes: 70351996
Fixes: 71443237
Test: packages/SystemUI/tests/src/com/android/systemui/statusbar/phone/ScrimControllerTest.java
Test: unlock wit fp. pattern
Test: pull down shade adjust brightness on bouncer and launcher
Test: unlock with fingerprint from pulsin notification