Handle the case of no grid options available am: 433e13b4

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/ThemePicker/+/21778919



Change-Id: I8d487be3f3fae062e61802e013deddc09b4805c1
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>