Add @MirrorsUsed annotations to speed up tests.

tests/lib/mirrors/generic_f_bounded_mixin_application_test.dart

 // Copyright (c) 2013, 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 test.generic_f_bounded;
 
+@MirrorsUsed(targets: "test.generic_f_bounded")
 import 'dart:mirrors';
 
 import 'package:expect/expect.dart';
 
 import 'generics_helper.dart';
 
 class Collection<C> {}
 class Serializable<S> {}
 
 class OrderedCollection<V>
@@ skipping 89 matching lines @@
   typeArguments(serializerDecl, []);
   typeArguments(collectionSerializerDecl, []);
   typeArguments(orderedCollectionSerializerDecl, []);
 
   typeArguments(orderedCollectionOfInt, [reflectClass(int)]);
   typeArguments(customOrderedCollectionOfInt, [reflectClass(int)]);
   typeArguments(serializerOfCollection, [collectionOfDynamic]);
   typeArguments(serializerOfOrderedCollection, [orderedCollectionOfDynamic]);
   typeArguments(collectionWithSerializableOfOrderedCollection, []);
 }