Merge changes from topic "multi_window_foreground_group" into main am: 766b0fbe

Original change: https://android-review.googlesource.com/c/platform/system/core/+/3210770



Change-Id: Ic354c626d5c4699e52be0e6daca6571a0de96632
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>