Let wallpaper get correct visibility and correct scrim color

Try to fix below:
1. Wallpaper is invisible in Keyguard because the state is still AOD.
2. Wallpaper is covered with scrim color in AOD because the alpha of
ScrimView is 1.

Bug: 113372444
Test: Manually and hierarchy viewer
Change-Id: I2d92ac585ccbee6b05cdbcdc3d514117a4c883db