Merge "Do not allow add view in DeferredAppWidgetHostView" into sc-v2-dev am: 83ba333604 am: 2789a69509

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/15401959

Change-Id: Iad5a96ac4e790e0d5eec8f0f65f28d8cabb6cd11