Merge "Make ClockRegistry and its provider singleton" into udc-dev am: df602e63

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/ThemePicker/+/23482074



Change-Id: Ieb25265f844e94779680bd7d34611cff0dbd5abc
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>