Dropped columns within a composite type were not handled correctly.
Also, we did not check for whether a composite result type had changed
since we cached the information about it.
Jan Urbański, per a bug report from Jean-Baptiste Quenot
This allows functions with multiple OUT parameters returning both one
or multiple records (RECORD or SETOF RECORD).
Jan Urbański, reviewed by Hitoshi Harada
of the previous monolithic setup-create-run sequence, that was apparently
inherited from a previous test infrastructure, but makes working with the
tests and adding new ones weird.
