Merge "Conform the logic to decide wallpaper darkness" into udc-dev am: 223a0a22 am: a172c094

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23617998



Change-Id: I61db3e10c05e5248c7b8ad5669a5ef8789df8478
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>