Workaround for 11854 (broken type check)

sdk/lib/js/dart2js/js_dart2js.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.
 
 library dart.js;
 
 import 'dart:_foreign_helper' show JS;
 import 'dart:_js_helper' show convertDartClosureToJS;
 
 JsObject get context {
@@ skipping 28 matching lines @@
   }
 
   JsFunction toJs() => new JsFunction._fromJs(_jsFunction);
 }
 
 class JsObject implements Serializable<JsObject> {
   final dynamic _jsObject;
 
   JsObject._fromJs(this._jsObject);
 
-  factory JsObject(Serializable<JsFunction> constructor, [List arguments]) {
+  // TODO(vsm): Type constructor as Serializable<JsFunction> when
+  // dartbug.com/11854 is fixed.
+  factory JsObject(var constructor, [List arguments]) {
     final constr = _convertToJS(constructor);
     if (arguments == null) {
       return new JsObject._fromJs(JS('=Object', 'new #()', constr));
     }
     final args = arguments.map(_convertToJS).toList();
     switch (args.length) {
       case 0:
         return new JsObject._fromJs(JS('=Object', 'new #()', constr));
       case 1:
         return new JsObject._fromJs(JS('=Object', 'new #(#)', constr, args[0]));
@@ skipping 68 matching lines @@
   operator==(other) => other is JsObject &&
       JS('bool', '# === #', _convertToJS(this), _convertToJS(other));
 
   bool hasProperty(String property) => JS('bool', '# in #', property,
       _convertToJS(this));
 
   void deleteProperty(String name) {
     JS('void', 'delete #[#]', _convertToJS(this), name);
   }
 
-  bool instanceof(Serializable<JsFunction> type) =>
+  // TODO(vsm): Type type as Serializable<JsFunction> when
+  // dartbug.com/11854 is fixed.
+  bool instanceof(var type) =>
       JS('bool', '# instanceof #', _convertToJS(this), _convertToJS(type));
 
   String toString() {
     try {
       return JS('String', '#.toString()', _convertToJS(this));
     } catch(e) {
       return super.toString();
     }
   }
 
@@ skipping 39 matching lines @@
       JS('bool', 'typeof # == "boolean" || # instanceof Boolean', o, o)) {
     return o;
   } else if (JS('bool', '# instanceof Function', o)) {
     return new JsFunction._fromJs(JS('=Object', '#', o));
   } else if (JS('bool', '# instanceof DartProxy', o)) {
     return JS('var', '#.o', o);
   } else {
     return new JsObject._fromJs(JS('=Object', '#', o));
   }
 }