Merge "Nullability check for spawn module" am: 022a139497

Original change: https://android-review.googlesource.com/c/platform/bionic/+/2516995

Change-Id: Id26022ebf8c920f43563e34a2ec4d090d744f41b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>