Merge "[2/n] Implement OpenTransparentActivityTest flicker test" into udc-qpr-dev am: 9e7ffd2ecc am: aa48459283

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23917799

Change-Id: Icf2a66b117df5bdf982399c9c6222d05e2f6c6be
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>