Merge "AssistContentRequester-weaken references to system callback" into sc-dev am: 7d54a31ba9 am: 18db32fcac

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/14413471

Change-Id: I0f1c7cc0ff4b60f794a7f36d083ba0729444efba