RESTRICT AUTOMERGE SurfaceFlinger: fix a potential race condition in stealReceiveChannel am: 0840cdd08f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/native/+/18766212

Change-Id: I4710ac999b560074a4cacbde6cf22ac1ad000e0d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>