Merge "Conform the logic to decide wallpaper darkness" into udc-dev am: 4f7f216c1f am: ede6dbc1ff

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/ThemePicker/+/23618530

Change-Id: Ifc336df01679f236f3bcbe92907051000858963c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>