Change how runtime type information is being set in the backend.

tests/language/factory_type_parameter_test.dart

Index: tests/language/factory_type_parameter_test.dart
===================================================================
--- tests/language/factory_type_parameter_test.dart	(revision 0)
+++ tests/language/factory_type_parameter_test.dart	(revision 0)
@@ -0,0 +1,42 @@
+// Copyright (c) 2012, 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<T> {
+  factory A.factory() {
+    return new B<Set>();
+  }
+
+  A();
+
+  build() {
+    return new A<T>();
+  }
+}
+
+class B<T> extends A<T> {
+  B();
+
+  build() {
+    return new B<T>();
+  }
+}
+
+main() {
+  Expect.isTrue(new A<List>() is A<List>);
+  Expect.isTrue(new A<List>.factory() is B<Set>);
+
+  // Check that we don't always return true for is checks with
+  // generics.
+  Expect.isFalse(new A<List>() is A<Set>);
+  Expect.isFalse(new A<List>.factory() is B<List>);
+
+  Expect.isTrue(new A<List>().build() is A<List>);
+  Expect.isFalse(new A<List>().build() is A<Set>);
+
+  Expect.isTrue(new A<List>.factory().build() is B<Set>);
+  Expect.isFalse(new A<List>.factory().build() is B<List>);
+
+  Expect.isTrue(new B<List>().build() is B<List>);
+  Expect.isFalse(new B<List>().build() is B<Set>);
+}