Fix bad assert in constant evaluation.

tests/language/indirect_const_null_test.dart

Index: tests/language/indirect_const_null_test.dart
diff --git a/tests/isolate/error_at_spawnuri_iso.dart b/tests/language/indirect_const_null_test.dart
similarity index 70%
copy from tests/isolate/error_at_spawnuri_iso.dart
copy to tests/language/indirect_const_null_test.dart
index b1650514fac895aea04bfe643a7fb182f0ce1ab3..51616143018a75078a0121f12937ddc0263ffc4a 100644
--- a/tests/isolate/error_at_spawnuri_iso.dart
+++ b/tests/language/indirect_const_null_test.dart
@@ -2,8 +2,9 @@
 // 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.
 
-library error_at_spawnuri_iso;
+import "package:expect/expect.dart";
 
 main() {
-  throw new ArgumentError("fast error");
+  const NULL = 1 == 1 ? null : false;
+  Expect.isNull(NULL);
 }