Migrate block 162 to Dart 2.0.

tests/language_2/type_variable_function_type_test.dart

 // Copyright (c) 2013, 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';
 
 typedef T Func<T>();
 
 class Foo<S> {
   m(x) => x is Func<S>;
 }
 
 class Bar<T> {
   f() {
     T local() {}
     return local;
   }
 }
 
 void main() {
-  var x = new Foo<List<String>>();
+  dynamic x = new Foo<List<String>>();
   if (new DateTime.now().millisecondsSinceEpoch == 42) x = new Foo<int>();
   Expect.isFalse(x.m(new Bar<String>().f()));
   Expect.isTrue(x.m(new Bar<List<String>>().f()));
 }