Fix errorprone warnings that should be errors am: 6aa0b94839 am: b7bfec8510 am: 06e6138127

Original change: https://android-review.googlesource.com/c/platform/test/mlts/benchmark/+/2254751

Change-Id: Id5b171c59bc58a49c99a0c657aff4349fc9f9730
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>