fix #27336, ddc with recursive generic class type args

pkg/dev_compiler/test/codegen/language/recursive_generic_test.dart

+// Copyright (c) 2016, 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";
+
+abstract class S<T extends S<T>> { m() => 123; get S_T => T; }
+class C<T extends C<T>> extends S<C> { m() => 456; get C_T => T; }
+
+main() {
+  Expect.equals(new C().m(), 456);
+  // TODO(jmesserly): this should be dart1 vs dart2, not DDC vs VM.
+  var isVM = const bool.fromEnvironment('dart.isVM');
+  Expect.equals(new C().S_T.toString(), isVM ? 'C' : 'C<C>');
+  Expect.equals(new C().C_T.toString(), isVM ? 'dynamic' : 'C');
+}