EXtjs 解决ie9 不支持extjs对象的 “createContextualFragment”属性或方法

if ((typeof Range !== "undefined") && !Range.prototype.createContextualFragment) {
Range.prototype.createContextualFragment = function (html) {
var frag = document.createDocumentFragment(),
div = document.createElement("div");
frag.appendChild(div);
div.outerHTML = html;
return frag;
};
}