isXMLDoc: function( elem ) {
// documentElement is verified for cases where it doesn't yet exist
// (such as loading iframes in IE - #4833)
- return ((elem.ownerDocument || elem).documentElement || 0).nodeName !== "HTML";
+ return ((elem ? elem.ownerDocument || elem : 0).documentElement || 0).nodeName !== "HTML";
},
// Evalulates a script in a global context