Change reflective serialization rules to be able to take type literals

pkg/serialization/test/no_library_test.dart

Index: pkg/serialization/test/no_library_test.dart
diff --git a/pkg/serialization/test/no_library_test.dart b/pkg/serialization/test/no_library_test.dart
index 30c10674adeba5a8b6dba6901d236509ef2c2ed6..33eeda1863ad093a555a4bf50fb3e954d8fc91a0 100644
--- a/pkg/serialization/test/no_library_test.dart
+++ b/pkg/serialization/test/no_library_test.dart
@@ -14,7 +14,7 @@ void main() {
   test("Serializing something without a library directive", () {
     var thing = new Thing()..name = 'testThing';
     var s = new Serialization()
-      ..addRuleFor(thing);
+      ..addRuleFor(Thing);
     var serialized = s.write(thing);
     var newThing = s.read(serialized);
     expect(thing.name, newThing.name);