Merge changes from topic "multi_window_foreground_group" into main am: 766b0fbe am: 9b3b5246

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



Change-Id: I2b983f311edae94935fec6f4ebb757bcfcac40fb
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>