Replace one FIXME with another. We handle protocols just fine now. The ObjC decl will only be 0 when we have an error on the ObjC decl. I would prefer we pass in a decl that is marked as invalid. I don't think this is critical to fix now, however I'd like us to be consistent. There are currently many places that don't mark the decl as invalid (which need to be fixed)...

llvm-svn: 42923