Merge "Polish entering pip from fullscreen with shell transition" into udc-dev...

Merge "Polish entering pip from fullscreen with shell transition" into udc-dev am: 16e51ba1 am: d5cc5aa1

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



Change-Id: I7f21b4bd22458d3e6dac067ea3e1d9e1f8ad4f1c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>