DrmHalTest: null check for skipped test am: 9049fc93a8 am: 6f60eece49

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2417394

Change-Id: I4349d1734c6efdf2eb68c86e1110f940ffcbffb7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>