Merge "Completely remove pinned task when starting a new PiP" into tm-dev am:...

Merge "Completely remove pinned task when starting a new PiP" into tm-dev am: bfbf74ae am: 420f7e1d am: 0d6a4a13

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18175783



Change-Id: I5504fe6a0f7a6b687d6806fccf9b6f9af12e9411
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>