Fixed tests so they do indeed confirm that values on optional named parameters are not allowed. Add…

tests/language/named_parameters8_negative_test.dart

Index: tests/language/named_parameters8_negative_test.dart
diff --git a/tests/language/named_parameters8_negative_test.dart b/tests/language/named_parameters8_negative_test.dart
index 3cea5fcc0b5764a68c43c61968ba9a394aa83c8f..bd26ff048c3dc8e15bb9bc6b70492890771fc7dd 100644
--- a/tests/language/named_parameters8_negative_test.dart
+++ b/tests/language/named_parameters8_negative_test.dart
@@ -14,7 +14,7 @@ class C {
   }
 }
 
-
 main() {
-  Expect.equals(true, false);
+  C c = new C();
+  c.InstallCallback(null);
 }