Fix failure reported by analyzer in test for issue 21159.

tests/language/issue21159_test.dart

 // Copyright (c) 2014, 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.
 
 import "package:expect/expect.dart";
 
 class C {
  get call => this;
 }
 
 // Recurs outside the try-block to avoid disabling inlining.
 foo() {
- new C()();
+ var c = new C();
+ c();
 }
 
 main() {
  bool exceptionCaught = false;
  try {
   foo();
  } on StackOverflowError catch (e) {
   exceptionCaught = true;
  }
  Expect.equals(true, exceptionCaught);
 }