Fix -Wnullable-to-nonnull-conversion errors am: 4730f0d7 am: 2e514606 am:...

Fix -Wnullable-to-nonnull-conversion errors am: 4730f0d7 am: 2e514606 am: d5881ece am: d01ac4af

Original change: https://android-review.googlesource.com/c/platform/packages/modules/DnsResolver/+/2582958



Change-Id: Id1f91d841d649da3831d7e31741bdd9b25bcc384
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>