Add lock to protect UnwantedInteractionBlocker am: a91d8576d9 am: 56fcab7171

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/native/+/18494314

Change-Id: Iac5871ee9b18f7a4cb07a9e9d567216ee6127925
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>