Merge "Null out Activity in split controller" into udc-qpr-dev am: 09892161 am: 87f6c0ae

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/24503472



Change-Id: Ie9425a34a99418852eb352e0d7da71a935f33674
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>