switch Node.bind to interop

pkg/template_binding/lib/src/element.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;
-
-/** Extensions to the [Element] API. */
-class _ElementExtension extends NodeBindExtension {
-  _ElementExtension(Element node) : super._(node);
-
-  bind(String name, value, {bool oneTime: false}) {
-    Element node = _node;
-
-    if (node is OptionElement && name == 'value') {
-      // Note: because <option> can be a semantic template, <option> will be
-      // a TemplateBindExtension sometimes. So we need to handle it here.
-      node.attributes.remove(name);
-
-      if (oneTime) return _updateOption(value);
-      _open(value, _updateOption);
-    } else {
-      bool conditional = name.endsWith('?');
-      if (conditional) {
-        node.attributes.remove(name);
-        name = name.substring(0, name.length - 1);
-      }
-
-      if (oneTime) return _updateAttribute(_node, name, conditional, value);
-
-      _open(value, (x) => _updateAttribute(_node, name, conditional, x));
-    }
-    return _maybeUpdateBindings(name, value);
-  }
-
-  void _updateOption(newValue) {
-    OptionElement node = _node;
-    var oldValue = null;
-    var selectBinding = null;
-    var select = node.parentNode;
-    if (select is SelectElement) {
-      var bindings = nodeBind(select).bindings;
-      if (bindings != null) {
-        var valueBinding = bindings['value'];
-        if (valueBinding is _InputBinding) {
-          selectBinding = valueBinding;
-          oldValue = select.value;
-        }
-      }
-    }
-
-    node.value = _sanitizeValue(newValue);
-
-    if (selectBinding != null && select.value != oldValue) {
-      selectBinding.value = select.value;
-    }
-  }
-}
-
-void _updateAttribute(Element node, String name, bool conditional, value) {
-  if (conditional) {
-    if (_toBoolean(value)) {
-      node.attributes[name] = '';
-    } else {
-      node.attributes.remove(name);
-    }
-  } else {
-    // TODO(jmesserly): escape value if needed to protect against XSS.
-    // See https://github.com/polymer-project/mdv/issues/58
-    node.attributes[name] = _sanitizeValue(value);
-  }
-}