Merge "Polish entering pip from fullscreen with shell transition" into udc-dev am: 16e51ba1

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22952408



Change-Id: I752b382e07acea0742baae3254e915f876dee488
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>