Implement type arguments in redirecting factories.

pkg/front_end/testcases/redirecting_factory_type_arguments.dart

Index: pkg/front_end/testcases/redirecting_factory_type_arguments.dart
diff --git a/pkg/front_end/testcases/redirecting_factory_type_arguments.dart b/pkg/front_end/testcases/redirecting_factory_type_arguments.dart
new file mode 100644
index 0000000000000000000000000000000000000000..582e9025ead3c0988c1910f7c1643d77e12e5a43
--- /dev/null
+++ b/pkg/front_end/testcases/redirecting_factory_type_arguments.dart
@@ -0,0 +1,32 @@
+// Copyright (c) 2017, 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.
+
+class A {}
+
+class B {}
+
+class C<C1, C2> {
+  factory C() = D<C2, C1>;
+}
+
+abstract class D<D1, D2> implements C<D2, D1> {
+  factory D() = E<D1, D2>;
+}
+
+class E<E1, E2> implements D<E1, E2> {
+  factory E() = F<E1, E2>;
+}
+
+class F<F1, F2> implements E<F1, F2> {
+  F();
+}
+
+main() {
+  "Should be F<B, A>";
+  new C<A, B>();
+  "Should be F<A, B>";
+  new D<A, B>();
+  "Should be F<A, B>";
+  new E<A, B>();
+}