Events operator [] shouldn't convert event name to lower case.

lib/dom/templates/html/frog/impl_EventTarget.darttemplate

 // 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 _EventsImpl implements Events {
   /* Raw event target. */
   // TODO(jacobr): it would be nice if we could specify this as
   // _EventTargetImpl or EventTarget
   final Dynamic _ptr;
 
   _EventsImpl(this._ptr);
 
-  _EventListenerListImpl operator [](String type) => _get(type.toLowerCase());
-  
-  _EventListenerListImpl _get(String type) {
+  _EventListenerListImpl operator [](String type) {

[Anton Muhin, 2012/06/05 13:47:03]

=> syntax?

     return new _EventListenerListImpl(_ptr, type);
   }
 }
 
 class _EventListenerListImpl implements EventListenerList {
   
   // TODO(jacobr): make this _EventTargetImpl
   final Dynamic _ptr;
   final String _type;
 
@@ skipping 28 matching lines @@
     _ptr.$dom_removeEventListener(_type, listener, useCapture);
   }
 }
 
 
 class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
 
   Events get on() => new _EventsImpl(this);
 $!MEMBERS
 }