Fix errorprone warnings that should be errors am: 8f8837c391

Original change: https://android-review.googlesource.com/c/platform/frameworks/layoutlib/+/2254826

Change-Id: Ic33fc60beeeb77f384b06891ab2d8acafd1564cb
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>