Just a follow up, I think what the problem had been was that my upgrade hadn't worked. It had given me an error, but then when I went to the APM, it looked like it had upgraded. Don't assume it's worked if you get errors!
What I had to do is manually go in and execute each line in psql, to make sure the data model was correct.
Michael's fix did work. Later, however, I upgraded again, and it still works. That means either that file was corrected, or fixing the data model fixed things. It's probably a good idea to check both.
