Change signature of lookupConstructor to only require a name.

pkg/compiler/lib/src/inferrer/simple_types_inferrer.dart

Index: pkg/compiler/lib/src/inferrer/simple_types_inferrer.dart
diff --git a/pkg/compiler/lib/src/inferrer/simple_types_inferrer.dart b/pkg/compiler/lib/src/inferrer/simple_types_inferrer.dart
index 0a3060e0f5377cd2cb0cecc260945b554dfa1e16..dea26fa211f661820f9fa7a305bb03d292db2a94 100644
--- a/pkg/compiler/lib/src/inferrer/simple_types_inferrer.dart
+++ b/pkg/compiler/lib/src/inferrer/simple_types_inferrer.dart
@@ -556,9 +556,7 @@ class SimpleTypeInferrerVisitor<T>
         if (!isConstructorRedirect
             && !seenSuperConstructorCall
             && !cls.isObject) {
-          Selector selector =
-              new Selector.callDefaultConstructor(analyzedElement.library);
-          FunctionElement target = cls.superclass.lookupConstructor(selector);
+          FunctionElement target = cls.superclass.lookupDefaultConstructor();
           analyzeSuperConstructorCall(target, new ArgumentsTypes([], {}));
           synthesizeForwardingCall(analyzedElement, target);
         }