Example showing alternate async measurement solution

client/html/src/EventTargetWrappingImplementation.dart

Index: client/html/src/EventTargetWrappingImplementation.dart
diff --git a/client/html/src/EventTargetWrappingImplementation.dart b/client/html/src/EventTargetWrappingImplementation.dart
index 573873a0d69d0bb898fb9f9d0acfbab21cebcc6a..944c699b03addbd215f1978ad530b0032a8e8408 100644
--- a/client/html/src/EventTargetWrappingImplementation.dart
+++ b/client/html/src/EventTargetWrappingImplementation.dart
@@ -1,4 +1,4 @@
-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// 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.
 
@@ -11,7 +11,7 @@ class EventsImplementation implements Events {
   EventsImplementation._wrap(this._ptr) {
     // TODO(sigmund): the key type (String) yields a warning in frog and the vm,
     // but it is currently necessary to compile with dartc.
-    _listenerMap = <String, EventListenerList>{};
+    _listenerMap = new Map<String, EventListenerList>();
   }
 
   EventListenerList operator [](String type) {