Setup initial device entry alpha based on curr keyguard state

Also add support for OFF => LOCKSCREEN transition.

Test: atest LockscreenNotificationsOverlapWithLockIcon
Fixes: 338476824
Flag: ACONFIG com.android.systemui.device_entry_udfps_refactor NEXTFOOD
Change-Id: Ic6bcaf2fed210378df6f9a5123583321c52ebb1c
3 files changed