Merge "Add a lock around any public methods in the AidlCallbackHandler." into udc-dev am: 51d0682216

Original change: https://googleplex-android-review.googlesource.com/c/platform/hardware/interfaces/+/22723736

Change-Id: I9ac3cd252d59cfd412cc2cbcbc3438560553512d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>