Add feature flag for remove smartspace default date am: 237d663b am: bb243c38

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/21532517



Change-Id: I511f4a649e4d75e1534cfd77f99f4c02a664169b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>