Fixed element upgrading for polymer

tools/dom/templates/html/impl/impl_HTMLDocument.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.
 
 // WARNING: Do not edit - generated code.
 
 part of $LIBRARYNAME;
 
 $(ANNOTATIONS)$(NATIVESPEC)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS {
 $!MEMBERS
@@ skipping 359 matching lines @@
       //
       //     var myProto = Object.create(HTMLElement.prototype);
       //     var myElement = document.registerElement('x-foo', {prototype: myProto});
       var baseElement = js.context[jsClassName];
       if (baseElement == null) {
         // Couldn't find the HTML element so use a generic one.
         baseElement = js.context['HTMLElement'];
       }
       var elemProto = js.context['Object'].callMethod("create", [baseElement['prototype']]);
 
+      // Remember for any upgrading done in wrap_jso.
+      _knownCustomeElements[tag] = customElementClass;
+
       // TODO(terry): Hack to stop recursion re-creating custom element when the
       //              created() constructor of the custom element does e.g.,
       //
       //                  MyElement.created() : super.created() {
       //                    this.innerHtml = "<b>I'm an x-foo-with-markup!</b>";
       //                  }
       //
       //              sanitizing causes custom element to created recursively
       //              until stack overflow.
       //
@@ skipping 98 matching lines @@
   /// parameter must be provided.
   @Experimental()
   ElementUpgrader createElementUpgrader(Type type, {String extendsTag}) {
 $if DART2JS
     return new _JSElementUpgrader(this, type, extendsTag);
 $else
     return new _VMElementUpgrader(this, type, extendsTag);
 $endif
   }
 }