Automatically generate most constructors

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

 // 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 ShadowRoot extends DocumentFragment {
+interface ShadowRoot extends DocumentFragment default _ShadowRootFactoryProvider {
+
+  ShadowRoot(Element host);
 
   final Element host;
 
   Element getElementById(String elementId);
 
   NodeList getElementsByClassName(String className);
 
   NodeList getElementsByTagName(String tagName);
 
   NodeList getElementsByTagNameNS(String namespaceURI, String localName);
 }