Merge "Add a flicker test for auto-enter pip from split screen." into udc-dev am: 01b189fb

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23503133



Change-Id: I88a0b593054915237f5d123b9f15537084b5a0ad
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>