Fixed broken snapshots for cells with background views

This isn't 100% ready but wanted to float it out there in case anyone has ideas: I fixed the bug where cells with background views don't display when swiping.

There's a catch, though: the separators aren't rendering in the simple case (no background view), which looks weird when the color background highlights itself—i.e. the separator turns green when hitting the trigger point.

Any suggestions for how to fix this pull to the point where it's worth accepting would be welcome.