Add artd unit tests. am: 9f4e1f04b5 am: 983dca9497 am: 9b92e69322 am: 5668c083b8

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

Change-Id: Ic12d33c4586b6f1c772d260de375ddf9e0359d68
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>