Merge "Respect the enforce flag for callback registration." into tm-qpr-dev am: a2c8daf7

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19563307



Change-Id: I1366d03a794ead35ba2a5aa3134306b4e0062399
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>