Merge "Nullability check for netdb module" am: 78b0558976

Original change: https://android-review.googlesource.com/c/platform/bionic/+/2522835

Change-Id: I3646c6512d4a12faa08e00f511cbfe9eb64df1ce
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>