Fixed an issue where the statusbar was made opaque even though it wasnt

Because on Pixel 4 and other devices, the light reveal scrim doesn't
have full alpha, the notification panel was marked opaque which removed
the wallpaper. This could lead to the wallpaper not being visible in
a couple of situations where it should have been, leaving AOD exposed.
Because of a separate bug (b/196306312), whenever the wallpaper is
hidden, we'd see a color layer, which would lead to the screen becoming
flickery and awake on AOD.

Fixes: 194760238
Test: atest SystemUITests
Merged-In: I5a7e80e2ced8f15f1b215549d0c051f1d61d2953
Change-Id: I5a7e80e2ced8f15f1b215549d0c051f1d61d2953
(cherry picked from commit d61e4732c78c56182dff98508c41f61871a3d939)
(cherry picked from commit 925211481c04e5861ce3b85e44f64bde09a67676)
6 files changed