Merge "Close assistant activities on closeSystemDialogs" into rvc-dev am: 9e639bb382 am: 1b85a98793 am: f8b6880e40

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11837612

Change-Id: I6cc699bcd5339cc9dfc3bd69684262a2e77dacf7