swift234

- Enhance SemaCoerce to work when DestTy is an unresolved type like "Unresolved -> Int".
   It still doesn't work for fully unstructured unresolved types.

- Enhance contextual resolution of UnresolvedMemberExpr to handle types like Unresolved->SomeOneOf.

- Enhance overload set resolution to work with types like "Unresolved->SomeTy", though this
  implementation is seems dubious to me and ignores type information that we have about the argument
  type.  I'd like to require the argument to also be a subtype, but I need to teach isSubtypeOf about
  unresolved types.  I'd love review of this code from someone.

- Add an if(0)'d out blob of code (which is close but not completely right) that handles coercing
  of applys with structure inference instead of syntactic inference, which will ultimately zap a 
  bunch of code and some FIXMEs.



Swift SVN r2008