Add missing case to ty_to_str.

Disable test that now fails because we produce undefined references to the
native functions.

Author: Rafael Avila de Espindola

src/Makefile

@@ -507,7 +507,6 @@ TEST_XFAILS_RUSTC := $(filter-out \
                         linear-for-loop.rs \
                         multiline-comment.rs \
                         mutual-recursion-group.rs \
-                        native2.rs \
                         obj-drop.rs \
                         obj-recursion.rs \
                         obj-with-vec.rs \

src/comp/middle/ty.rs

@@ -210,6 +210,7 @@ fn ty_to_str(&@t typ) -> str {
     }
 
     alt (typ.struct) {
+        case (ty_native)       { s = "native";                    }
         case (ty_nil)          { s = "()";                        }
         case (ty_bool)         { s = "bool";                      }
         case (ty_int)          { s = "int";                       }