Merge "Add a SysPropBooleanFlag for the lockscreen-lwp project." into udc-dev am: d765772c am: 3da81518

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22037003



Change-Id: I9dd7b22db6e56d184efcbeb22778621d0c878b1e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>