Merge "Move the pinned task to front when dismissed split-screen" into rvc-dev am: 92d8d6c384 am: 9b2e5941ad am: 1cbf002f46 am: f63dffa7d3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/12034169

Change-Id: Ibee209c8fe469267367b7204c8c9c38f8ba6cc2e