Fix bugprone-unused-return-value clang-tidy issues am: 94383b4038 am: d4759e125c am: 72a08a3384

Original change: https://android-review.googlesource.com/c/platform/art/+/2203655

Change-Id: Ibeff3a74d6f8036cc20707df62d11e3c4301e752
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>