Show measure bars when StaffSymbol #'line-count = #1

Question

(I can't tell if this is meant to be SO or SU, so please move it as necessary.)

Lilypond automatically puts in measure bars for me, but only if there's more than one line. I'm writing a part for which I'm doing:

\override StaffSymbol #'line-count = #1

and measure bars do not appear. (That's kind of odd: just because there's no pitch on this part, doesn't mean counting measures is any less important.)

How do I tell Lilypond to draw measure bars?

Answer 1

Found a solution:

\override BarLine #'bar-size = #4