Add VTS for Watermark APIs am: 17a9190730 am: a311d90492

Original change: https://googleplex-android-review.googlesource.com/c/platform/hardware/interfaces/+/23303872

Change-Id: Ieedc6f2497308dc461c81aff6197829faa0ee6bf
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>