swift234

fix FailureDiagnosis::collectCalleeCandidateInfo to look at the entire
disjunction candidate set for a constraint that fails to match, not just
a single Bind within it.  This eliminates the arbitrary nature of picking
one match, allowing us to diagnose the entire candidate set.

This exposed that we were trying to do argument matching of 'self' against
the partially curried arguments.  Adjust the hack we have for that a bit to
make things work, but there are bigger problems for argument matching that
will need to be addressed.


Swift SVN r30064