Merge "Add a feature flag for smartspace dismiss option." into sc-dev am: 7274d29c4c am: e9396a7f13

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/14252388

Change-Id: Ib2115b050db4eef014d482a75c9edd5049a363a7