Merge "If leash is null it's not a valid state to remove PiP" into udc-dev am: fae4039c

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22683283



Change-Id: Icfce7211111549e514d211239bcd335600611f6c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>