Fix SystemUtil.withProperty documentation and consistent API with other utils am: 00686f1e88 am: 77cab01de8 am: 282dcd9ea5 am: c943fde680 am: d320008a20 am: 6e7b51909f am: 29ce4a2a44 am: fe72b5f50e am: fdce96c894 am: fc73936b12 am: 304805e51b

Original change: https://googleplex-android-review.googlesource.com/c/platform/platform_testing/+/20591585

Change-Id: I3cac4652c26843152f25d9b56d46b7bcd007dd5c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>