Delete a variant from the table, and the last one warns you first

The variants table inside the product editor now has Delete on each row, so you can remove one without opening it or selecting it first. Duplicate is still in the variant editor's menu. And when the variant you delete is the product's last one, the confirmation now warns you first wherever you delete it from, the editor included. It asks whether to remove all variants, and says that all variant data, identifiers, listings and images go with it. The product becomes a simple product again.