Merge "Adjust testMutate to not rely on undefined behavior" into oreo-mr1-cts-dev am: 1da7e4eff4 am: 70a8ecddef am: 1d95819567 am: ec2eae8f95 am: 78860e077c am: 060b5813ed am: aec5692dc7

Original change: https://android-review.googlesource.com/c/platform/cts/+/1810497

Change-Id: I12bf7ca10c06d6da60d60f92e896b0c13b8ae297