Fix how displays are used in test cases am: 017cb98e am: b536f21f am:...

Fix how displays are used in test cases am: 017cb98e am: b536f21f am: f1ccb718 am: a613b2e8 am: 7f602c36

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2305821



Change-Id: I0fe7d3555aebb790949edafcb36521ca1805abec
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>