Merge "Implement Observe Mode and Preferred Service event listeners with...

Merge "Implement Observe Mode and Preferred Service event listeners with functional callbacks." into main am: 7b40a103 am: fff7f91e

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/3323976



Change-Id: I1880d815d62d587ca785520836f78a91d584cb6c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>