If a PRIMARY_BOUNCER->LOCKSCREEN is running...

... don't process shade alpha request. This can happen when
you swipe down and enabled the setting to disable notifs on
lockscreen. This will pop up the bouncer, and swiping back
should be smooth.

Fixes: 342528378
Test: atest KeyguardRootViewModelTest
Flag: com.android.systemui.keyguard_bottom_area_refactor
Change-Id: Idda37d4e811973e879b9a3df21503f11cbf2d4a6