Merge "Add test for service callback" am: cacf08f6f7

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2392835

Change-Id: I3550c257a43ffc9f8ec796bfbcf84e28aa078a01
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>