polymer -- fix for ie10

pkg/polymer/lib/src/instance.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 polymer;
 
 /// Use this annotation to publish a field as an attribute.
 ///
 /// You can also use [PublishedProperty] to provide additional information,
 /// such as automatically syncing the property back to the attribute.
@@ skipping 114 matching lines @@
     // Our normal registration, this will queue up the name->type association.
     register(name, type);
 
     // Build a polymer-element and initialize it to register
     if (doc == null) doc = document;
     var poly = doc.createElement('polymer-element');
     poly.attributes['name'] = name;
     if (extendsTag != null) poly.attributes['extends'] = extendsTag;
     if (template != null) poly.append(template);
 
-    new JsObject.fromBrowserObject(poly).callMethod('init');
+    // TODO(jmesserly): conceptually this is just:
+    //     new JsObject.fromBrowserObject(poly).callMethod('init')
+    //
+    // However doing it that way hits an issue with JS-interop in IE10: we get a
+    // JsObject that wraps something other than `poly`, due to improper caching.
+    // By reusing _polymerElementProto that we used for 'register', we can
+    // then call apply on it to invoke init() with the correct `this` pointer.
+    JsFunction init = _polymerElementProto['init'];
+    init.apply([], thisArg: poly);
   }
 
   // Note: these are from src/declaration/import.js
   // For now proxy to the JS methods, because we want to share the loader with
   // polymer.js for interop purposes.
   static Future importElements(Node elementOrFragment) {
     var completer = new Completer();
     js.context['Polymer'].callMethod('importElements',
         [elementOrFragment, () => completer.complete()]);
     return completer.future;
@@ skipping 964 matching lines @@
 
 final Logger _observeLog = new Logger('polymer.observe');
 final Logger _eventsLog = new Logger('polymer.events');
 final Logger _unbindLog = new Logger('polymer.unbind');
 final Logger _bindLog = new Logger('polymer.bind');
 
 final Expando _eventHandledTable = new Expando<Set<Node>>();
 
 final JsObject _PolymerGestures = js.context['PolymerGestures'];