Build only the needed run-test shards with "test.py -b -t XXX" am: b7b5fe5b36

Original change: https://android-review.googlesource.com/c/platform/art/+/2209544

Change-Id: I0e45072a16a0aa500470c437a3b41de7ef45672c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>