The source code

    /*!
     * Ext JS Library 3.4.0
     * Copyright(c) 2006-2011 Sencha Inc.
     * licensing@sencha.com
     * http://www.sencha.com/license
     */
    /**
     * @class Ext.Element
     */
    Ext.Element.addMethods({
        /**
         * Stops the specified event(s) from bubbling and optionally prevents the default action
         * @param {String/Array} eventName an event / array of events to stop from bubbling
         * @param {Boolean} preventDefault (optional) true to prevent the default action too
         * @return {Ext.Element} this
         */
        swallowEvent : function(eventName, preventDefault) {
            var me = this;
            function fn(e) {
                e.stopPropagation();
                if (preventDefault) {
                    e.preventDefault();
                }
            }

            if (Ext.isArray(eventName)) {
                Ext.each(eventName, function(e) {
                     me.on(e, fn);
                });
                return me;
            }
            me.on(eventName, fn);
            return me;
        },

        /**
         * Create an event handler on this element such that when the event fires and is handled by this element,
         * it will be relayed to another object (i.e., fired again as if it originated from that object instead).
         * @param {String} eventName The type of event to relay
         * @param {Object} object Any object that extends {@link Ext.util.Observable} that will provide the context
         * for firing the relayed event
         */
        relayEvent : function(eventName, observable) {
            this.on(eventName, function(e) {
                observable.fireEvent(eventName, e);
            });
        },

        /**
         * Removes worthless text nodes
         * @param {Boolean} forceReclean (optional) By default the element
         * keeps track if it has been cleaned already so
         * you can call this over and over. However, if you update the element and
         * need to force a reclean, you can pass true.
         */
        clean : function(forceReclean) {
            var me  = this,
                dom = me.dom,
                n   = dom.firstChild,
                ni  = -1;

            if (Ext.Element.data(dom, 'isCleaned') && forceReclean !== true) {
                return me;
            }

            while (n) {
                var nx = n.nextSibling;
                if (n.nodeType == 3 && !(/\S/.test(n.nodeValue))) {
                    dom.removeChild(n);
                } else {
                    n.nodeIndex = ++ni;
                }
                n = nx;
            }

            Ext.Element.data(dom, 'isCleaned', true);
            return me;
        },

        /**
         * Direct access to the Updater {@link Ext.Updater#update} method. The method takes the same object
         * parameter as {@link Ext.Updater#update}
         * @return {Ext.Element} this
         */
        load : function() {
            var updateManager = this.getUpdater();
            updateManager.update.apply(updateManager, arguments);

            return this;
        },

        /**
        * Gets this element's {@link Ext.Updater Updater}
        * @return {Ext.Updater} The Updater
        */
        getUpdater : function() {
            return this.updateManager || (this.updateManager = new Ext.Updater(this));
        },

        /**
        * Update the innerHTML of this element, optionally searching for and processing scripts
        * @param {String} html The new HTML
        * @param {Boolean} loadScripts (optional) True to look for and process scripts (defaults to false)
        * @param {Function} callback (optional) For async script loading you can be notified when the update completes
        * @return {Ext.Element} this
         */
        update : function(html, loadScripts, callback) {
            if (!this.dom) {
                return this;
            }
            html = html || "";

            if (loadScripts !== true) {
                this.dom.innerHTML = html;
                if (typeof callback == 'function') {
                    callback();
                }
                return this;
            }

            var id  = Ext.id(),
                dom = this.dom;

            html += '';

            Ext.lib.Event.onAvailable(id, function() {
                var DOC    = document,
                    hd     = DOC.getElementsByTagName("head")[0],
                    re     = /(?:]*)?>)((\n|\r|.)*?)(?:<\/script>)/ig,
                    srcRe  = /\ssrc=([\'\"])(.*?)\1/i,
                    typeRe = /\stype=([\'\"])(.*?)\1/i,
                    match,
                    attrs,
                    srcMatch,
                    typeMatch,
                    el,
                    s;

                while ((match = re.exec(html))) {
                    attrs = match[1];
                    srcMatch = attrs ? attrs.match(srcRe) : false;
                    if (srcMatch && srcMatch[2]) {
                       s = DOC.createElement("script");
                       s.src = srcMatch[2];
                       typeMatch = attrs.match(typeRe);
                       if (typeMatch && typeMatch[2]) {
                           s.type = typeMatch[2];
                       }
                       hd.appendChild(s);
                    } else if (match[2] && match[2].length > 0) {
                        if (window.execScript) {
                           window.execScript(match[2]);
                        } else {
                           window.eval(match[2]);
                        }
                    }
                }

                el = DOC.getElementById(id);
                if (el) {
                    Ext.removeNode(el);
                }

                if (typeof callback == 'function') {
                    callback();
                }
            });
            dom.innerHTML = html.replace(/(?:)((\n|\r|.)*?)(?:<\/script>)/ig, "");
            return this;
        },

        // inherit docs, overridden so we can add removeAnchor
        removeAllListeners : function() {
            this.removeAnchor();
            Ext.EventManager.removeAll(this.dom);
            return this;
        },

        /**
         * Creates a proxy element of this element
         * @param {String/Object} config The class name of the proxy element or a DomHelper config object
         * @param {String/HTMLElement} renderTo (optional) The element or element id to render the proxy to (defaults to document.body)
         * @param {Boolean} matchBox (optional) True to align and size the proxy to this element now (defaults to false)
         * @return {Ext.Element} The new proxy element
         */
        createProxy : function(config, renderTo, matchBox) {
            config = (typeof config == 'object') ? config : {tag : "div", cls: config};

            var me = this,
                proxy = renderTo ? Ext.DomHelper.append(renderTo, config, true) :
                                   Ext.DomHelper.insertBefore(me.dom, config, true);

            if (matchBox && me.setBox && me.getBox) { // check to make sure Element.position.js is loaded
               proxy.setBox(me.getBox());
            }
            return proxy;
        }
    });

    Ext.Element.prototype.getUpdateManager = Ext.Element.prototype.getUpdater;