Add artd unit tests. am: 9f4e1f04b5 am: 983dca9497 am: 9b92e69322

Original change: https://android-review.googlesource.com/c/platform/art/+/2129473

Change-Id: Ic20c99d420005715548e35f9a4d0d8dca57b7be2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>