swift234

Two changes to the ASTDumper:
1. Do not call getInterfaceType() on a decl if it isn't already set, since
   this will cause it to be lazily computed, and it would be nice for the
   ASTDumper to not side-effect our AST.

2. Print the interface type of a decl if present, even if the type is not.
   Surprisingly to me, we compute the interface type a lot sooner than the type
   for a decl in some cases.



Swift SVN r14951