Update copyright in dart:dom interface templates

client/dom/generated/src/interface/XMLHttpRequest.dart

-// 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.
 
 // WARNING: Do not edit - generated code.
 
 interface XMLHttpRequest extends EventTarget default _XMLHttpRequestFactoryProvider {
 
   XMLHttpRequest();
 
 
@@ skipping 42 matching lines @@
   void open(String method, String url, [bool async, String user, String password]);
 
   void overrideMimeType(String override);
 
   void removeEventListener(String type, EventListener listener, [bool useCapture]);
 
   void send([var data]);
 
   void setRequestHeader(String header, String value);
 }