Merge "Migrate reigster service callback backend" am: ee0e6cd701 am: 5b610505d0

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2424806

Change-Id: Ie0cdd0b32a01cd0d855493277f2debb863591d41
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>