swift234

IRGen: Instantiate ObjC metaclasses and rodata with generic classes.

If we officially register our classes with the ObjC runtime, we can't get away with generic class instances sharing a runtime name or a metaclass anymore, so pack the metaclass and rodata templates into the generic metadata template and add codegen to the fill function to wire up the references at instantiation time. Since we don't have a runtime mangler yet, create a stupid unique name for classes by tacking on the pointer value.

Swift SVN r17882