When generating the error message, don't overrun args.nodes .

tests/language/src/Constructor3NegativeTest.dart

Index: tests/language/src/Constructor3NegativeTest.dart
===================================================================
--- tests/language/src/Constructor3NegativeTest.dart	(revision 0)
+++ tests/language/src/Constructor3NegativeTest.dart	(revision 0)
@@ -0,0 +1,17 @@
+// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Check that there's no crash when constructor called with wrong
+// number of args.
+
+
+class Klass {
+  Klass(var v) {}
+}
+
+
+main() {
+  var k = new Klass();
+  var l = new Klass(1, 2);
+}