Merge the work on Generic Types Reification from 'dart-lang/reify' repo

pkg/kernel/testcases/reify/factories_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.
+
+library factories_test;
+
+import 'test_base.dart';
+
+class A<T> {
+  factory A() {
+    return new B<T>();
+  }
+
+  factory A.named() {
+    return new A<T>.internal();
+  }
+
+  factory A.forward() = A<T>.internal;
+
+  A.internal();
+}
+
+class B<T> extends A<T> {
+  B() : super.internal();
+}
+
+class X {}
+
+class Y {}
+
+main() {
+  expectTrue(new A<X>.named() is A<X>);
+  expectTrue(new A<X>.named() is! A<Y>);
+  expectTrue(new A<X>.forward() is A<X>);
+  expectTrue(new A<X>.forward() is! A<Y>);
+  expectTrue(new A<X>() is B<X>);
+  expectTrue(new A<X>() is! B<Y>);
+  expectTrue(new A<X>.named() is! B<X>);
+  expectTrue(new A<X>.forward() is! B<X>);
+}