automatically clean up CompoundBinding

pkg/mdv/lib/src/template_iterator.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 mdv;
 
 // This code is a port of Model-Driven-Views:
 // https://github.com/polymer-project/mdv
 // The code mostly comes from src/template_element.js
 
@@ skipping 367 matching lines @@
   void unobserve() {
     if (_sub == null) return;
     _sub.cancel();
     _sub = null;
   }
 
   void close() {
     if (closed) return;
 
     unobserve();
+    inputs.close();
     terminators.clear();
-    inputs.dispose();
     closed = true;
   }
 
   static void _unbindAllRecursively(Node node) {
     var nodeExt = _mdv(node);
     nodeExt._templateInstance = null;
     if (node is Element && (node as Element).isTemplate) {
       // Make sure we stop observing when we remove an element.
       var templateIterator = nodeExt._templateIterator;
       if (templateIterator != null) {
         templateIterator.close();
         nodeExt._templateIterator = null;
       }
     }
 
     _nodeOrCustom(node).unbindAll();
     for (var c = node.firstChild; c != null; c = c.nextNode) {
       _unbindAllRecursively(c);
     }
   }
 }