Merge "Conform the logic to decide wallpaper darkness" into udc-dev am: 4f7f216c1f am: 5113509114 am: 388b2b91a2

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

Change-Id: I6371fba62f5aa6db98fd08a7d42ca9eee3978201
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>