swift234

Teach scalar-to-tuple conversions to use the resilient entry points for default arguments.

There is a bunch of copy-and-paste here from the tuple-shuffle
code. The expected trajectory is that ScalarToTupleExpr will grow into
a general TupleConversionExpr, obviating the need for TupleShuffleExpr
entirely and eliminating the redundancy.



Swift SVN r6347