[automerger skipped] C2AllocatorIon:protect mMappings using mutex am: 416da6e8da am: 670024887e am: d6545589e2 am: 1785465c71 am: 89342cbdfa -s ours

am skip reason: Merged-In I24e53629d5a6dfad22b84dd2278eb1a288c9ab35 with SHA-1 416da6e8da is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/av/+/16622627

Change-Id: Ie618cf93e8ddb5e294570f45534d39d806290cbb