Merge "Nullability check for msg module." am: a1ff2e6159

Original change: https://android-review.googlesource.com/c/platform/bionic/+/2539230

Change-Id: I0bc51745c966809f5939159ff48ea88918667ec7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>