1. Deprecated("Internal Use Only")
Map<String, dynamic> convertNativeObjectToDartMap(JsObject jsObject)

Source 

@Deprecated("Internal Use Only")
Map<String, dynamic> convertNativeObjectToDartMap(js.JsObject jsObject) {
  var result = new Map();
  var keys = js.JsNative.callMethod(js.JsNative.getProperty(js.context, 'Object'), 'keys', [jsObject]);
  for (var key in keys) {
    result[key] = js.JsNative.getProperty(jsObject, key);
  }
  return result;
}