swift234

A couple of 'throws' inference fix-ups:
- When inferring 'throws' for a closure function type, look inside of catchless do blocks for 'try' expressions.
- When simplifying overload constriants for applications of throwing initializers, the bound member type of the initializer should also be marked as throwing.
  (Not doing so would cause us to incorrectly reject the overload.)

Swift SVN r27568