I considered this at first, but decided to keep it simple until it
turned out to matter. Oops, it already matters, lol!
I want the item search code to be able to easily tell if the series
name is real or a placeholder, so we can decide whether to build the
filter text in `fits:$series-$color-$species` form or
`fits:alt-style-$id` form.
So in this change, we keep it that `AltStyle#series_name` returns the
placeholder string if none is set, but callers can explicitly ask
whether it's a real series name or not. Will use this in our next
change!
Emi Matchu
18c7a34b8f