update TemplateBinding and Custom Elements polyfills

pkg/template_binding/lib/src/instance_binding_map.dart

 // Copyright (c) 2013, 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.
 
 part of template_binding;
 
 class _InstanceBindingMap {
   final List bindings;
   final List<_InstanceBindingMap> children;
   final Node templateRef;
-  final bool hasSubTemplate;
 
-  _InstanceBindingMap._(this.bindings, this.children, this.templateRef,
-      this.hasSubTemplate);
+  _InstanceBindingMap._(this.bindings, this.children, this.templateRef);
 
   factory _InstanceBindingMap(Node node, BindingDelegate delegate) {
     var bindings = _getBindings(node, delegate);
-
-    bool hasSubTemplate = false;
     Node templateRef = null;
 
-    if (isSemanticTemplate(node)) {
-      templateRef = node;
-      hasSubTemplate = true;
-    }
+    if (isSemanticTemplate(node)) templateRef = node;
 
     List children = null;
     for (var c = node.firstChild, i = 0; c != null; c = c.nextNode, i++) {
       var childMap = new _InstanceBindingMap(c, delegate);
       if (childMap == null) continue;
 
       if (children == null) children = new List(node.nodes.length);
       children[i] = childMap;
-      if (childMap.hasSubTemplate) {
-        hasSubTemplate = true;
-      }
     }
 
-    return new _InstanceBindingMap._(bindings, children, templateRef,
-        hasSubTemplate);
+    return new _InstanceBindingMap._(bindings, children, templateRef);
   }
 }
 
 
 void _addMapBindings(Node node, _InstanceBindingMap map, model,
     BindingDelegate delegate, List bound) {
   if (map == null) return;
 
   if (map.templateRef != null) {
     TemplateBindExtension.decorate(node, map.templateRef);
     if (delegate != null) {
       templateBindFallback(node)._bindingDelegate = delegate;
     }
   }
 
   if (map.bindings != null) {
     _processBindings(map.bindings, node, model, bound);
   }
 
   if (map.children == null) return;
 
   int i = 0;
   for (var c = node.firstChild; c != null; c = c.nextNode) {
     _addMapBindings(c, map.children[i++], model, delegate, bound);
   }
 }