Add @MirrorsUsed annotations to speed up tests.

tests/lib/mirrors/delegate_function_invocation_test.dart

 // Copyright (c) 2014, 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.delgate_function_invocation;
+library test.delegate_function_invocation;
 
+@MirrorsUsed(targets: "test.delegate_function_invocation")
 import 'dart:mirrors';
 
 import 'package:expect/expect.dart';
 
 class Proxy {
   var targetMirror;
   Proxy(target) : this.targetMirror = reflect(target);
   noSuchMethod(invocation) => targetMirror.delegate(invocation);
 }
 
@@ skipping 30 matching lines @@
   Expect.equals(45, proxy());
   Expect.equals(45, proxy.call());
 }
 
 main() {
   testClosure();
   testFakeFunction();
   testTopLevelTearOff();
   testInstanceTearOff();
 }