Remove support for attribute event listeners.

client/dom/generated/src/wrapping/_AbstractWorkerWrappingImplementation.dart

 // Copyright (c) 2011, 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.
 
 // WARNING: Do not edit - generated code.
 
 class _AbstractWorkerWrappingImplementation extends DOMWrapperBase implements AbstractWorker {
   _AbstractWorkerWrappingImplementation() : super() {}
 
   static create__AbstractWorkerWrappingImplementation() native {
     return new _AbstractWorkerWrappingImplementation();
   }
 
-  EventListener get onerror() { return _get_onerror(this); }
-  static EventListener _get_onerror(var _this) native;
-
-  void set onerror(EventListener value) { _set_onerror(this, value); }
-  static void _set_onerror(var _this, EventListener value) native;
-
   void addEventListener(String type, EventListener listener, [bool useCapture = null]) {
     if (useCapture === null) {
       _addEventListener_AbstractWorker(this, type, listener);
       return;
     } else {
       _addEventListener_AbstractWorker_2(this, type, listener, useCapture);
       return;
     }
   }
   static void _addEventListener_AbstractWorker(receiver, type, listener) native;
@@ skipping 11 matching lines @@
     } else {
       _removeEventListener_AbstractWorker_2(this, type, listener, useCapture);
       return;
     }
   }
   static void _removeEventListener_AbstractWorker(receiver, type, listener) native;
   static void _removeEventListener_AbstractWorker_2(receiver, type, listener, useCapture) native;
 
   String get typeName() { return "AbstractWorker"; }
 }