Merge "Refine Style/Grid picker recyclerview layout" into ub-launcher3-master am: b3c2a0dd24 am: 85f2f44afe

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/ThemePicker/+/12097141

Change-Id: I98c17ecd1b7cdbfccf70b672e682cd7a5ca06f21