[automerger skipped] Extract common test functionality to new class am: d655e5b5 am: 0ce3a88f -s ours

am skip reason: Merged-In Idffddb499880fd4071db9499fafb87d3e116c701 with SHA-1 f81d7439 is already in history

Original change: https://android-review.googlesource.com/c/platform/frameworks/libs/systemui/+/3326134



Change-Id: I8f1cf6b6742cf15fef6e02dd3cc644a4124d58be
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>