Migrate block 116.

tests/language_strong/if_null_assignment_helper.dart

-// Copyright (c) 2015, 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.
-
-// Library used by if_null_assignment_behavior_test.dart, which
-// imports it using the prefix "h.".
-
-library lib;
-
-import "package:expect/expect.dart";
-
-List<String> operations = [];
-
-var xGetValue = null;
-
-get x {
-  operations.add('h.x');
-  var tmp = xGetValue;
-  xGetValue = null;
-  return tmp;
-}
-
-void set x(value) {
-  operations.add('h.x=$value');
-}
-
-class C {
-  static var xGetValue = null;
-
-  static get x {
-    operations.add('h.C.x');
-    var tmp = xGetValue;
-    xGetValue = null;
-    return tmp;
-  }
-
-  static void set x(value) {
-    operations.add('h.C.x=$value');
-  }
-}