Comment 16 for bug 1457126

Here's a patch that should do what you suggested. I also wanted to add the tooltips su_v wanted, however, GTK doesn't seem to support that.
I use a somewhat ugly nesting of std:: containers instead of creating a new class type, but given it's only used to pass information between very few places I think it's ok like this. If you feel that it's not clean enough I can probably come up with something more sophisticated instead.