[automerged blank] C2Allocator: protetct memory mappings from race condition...

[automerged blank] C2Allocator: protetct memory mappings from race condition 2p: 5cbca291 2p: 1d42f8d4

Blank merge reason: Change-Id Icf6d00491438176e9092b67974a9388e803ac130 with SHA-1 530a22aa is in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/av/+/17806584

Bug: 213850092
Change-Id: If4a9c08dde1f82218063400c0e1ff4b40828c289
Merged-In: Icf6d00491438176e9092b67974a9388e803ac130