Merge "Move the pinned task to front when dismissed split-screen" into rvc-dev am: 92d8d6c384 am: c10b144bc2

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

Change-Id: I4e7f2a35d2668e4f6eab4fd7865f02cd89d778d2