I've enabled mod_pagespeed, and now get this extra javascript added around the place where my HTML logo is defined. I'm not sure what this code does and how I can disable it?

<a href=http://www.example.com/ id=logo><script pagespeed_no_defer=>//<![CDATA[

(function(){var g=this,h=function(b,d){var a=b.split(.),c=g;a[0]in c||!c.execScript||c.execScript(var +a[0]);for(var e;a.length&&(e=a.shift());)a.length||void 0===d?c[e]?c=c[e]:c=c[e]={}:c[e]=d};var l=function(b){var d=b.length;if(0<d){for(var a=Array(d),c=0;c<d;c++)a[c]=b[c];return a}return[]};var m=function(b){var d=window;if(d.addEventListener)d.addEventListener(load,b,!1);else if(d.attachEvent)d.attachEvent(onload,b);else{var a=d.onload;d.onload=function(){b.call(this);a&&a.call(this)}}};var n,p=function(b,d,a,c,e){this.f=b;this.h=d;this.i=a;this.c=e;this.e={height:window.innerHeight||document.documentElement.clientHeight||document.body.clientHeight,width:window.innerWidth||document.documentElement.clientWidth||document.body.clientWidth};this.g=c;this.b={};this.a=[];this.d={}},q=function(b,d){var a,c,e=d.getAttribute(pagespeed_url_hash);if(a=e&&!(e in b.d))if(0>=d.offsetWidth&&0>=d.offsetHeight)a=!1;else{c=d.getBoundingClientRect();var f=document.body;a=c.top+(pageYOffsetin window?window.pageYOffset:(document.documentElement||f.parentNode||f).scrollTop);c=c.left+(pageXOffsetin window?window.pageXOffset:(document.documentElement||f.parentNode||f).scrollLeft);f=a.toString()+,+c;b.b.hasOwnProperty(f)?a=!1:(b.b[f]=!0,a=a<=b.e.height&&c<=b.e.width)}a&&(b.a.push(e),b.d[e]=!0)};p.prototype.checkImageForCriticality=function(b){b.getBoundingClientRect&&q(this,b)};h(pagespeed.CriticalImages.checkImageForCriticality,function(b){n.checkImageForCriticality(b)});h(pagespeed.CriticalImages.checkCriticalImages,function(){r(n)});var r=function(b){b.b={};for(var d=[IMG,INPUT],a=[],c=0;c<d.length;++c)a=a.concat(l(document.getElementsByTagName(d[c])));if(0!=a.length&&a[0].getBoundingClientRect){for(c=0;d=a[c];++c)q(b,d);a=oh=+b.i;b.c&&(a+=&n=+b.c);if(d=0!=b.a.length)for(a+=&ci=+encodeURIComponent(b.a[0]),c=1;c<b.a.length;++c){var e=,+encodeURIComponent(b.a[c]);131072>=a.length+e.length&&(a+=e)}b.g&&(e=&rd=+encodeURIComponent(JSON.stringify(s())),131072>=a.length+e.length&&(a+=e),d=!0);t=a;if(d){c=b.f;b=b.h;var f;if(window.XMLHttpRequest)f=new XMLHttpRequest;else if(window.ActiveXObject)try{f=new ActiveXObject(Msxml2.XMLHTTP)}catch(k){try{f=new ActiveXObject(Microsoft.XMLHTTP)}catch(u){}}f&&(f.open(POST,c+(-1==c.indexOf(?)??:&)+url=+encodeURIComponent(b)),f.setRequestHeader(Content-Type,application/x-www-form-urlencoded),f.send(a))}}},s=function(){var b={},d=document.getElementsByTagName(IMG);if(0==d.length)return{};var a=d[0];if(!(naturalWidthin a&&naturalHeightin a))return{};for(var c=0;a=d[c];++c){var e=a.getAttribute(pagespeed_url_hash);e&&(!(e in b)&&0<a.width&&0<a.height&&0<a.naturalWidth&&0<a.naturalHeight||e in b&&a.width>=b[e].k&&a.height>=b[e].j)&&(b[e]={rw:a.width,rh:a.height,ow:a.naturalWidth,oh:a.naturalHeight})}return b},t=;h(pagespeed.CriticalImages.getBeaconData,function(){return t});h(pagespeed.CriticalImages.Run,function(b,d,a,c,e,f){var k=new p(b,d,a,e,f);n=k;c&&m(function(){window.setTimeout(function(){r(k)},0)})});})();pagespeed.CriticalImages.Run('/mod_pagespeed_beacon','http://www.example.com/slug','SLoDkQnME-',true,false,'gxYRJPh80JY');

//]]></script><img src=http://www.example.com/xlogo.png.pagespeed.ic.GAQP-mof5d.png alt=Logo pagespeed_url_hash=4083345942 onload=pagespeed.CriticalImages.checkImageForCriticality(this);></a>

Here's a fiddle: http://jsfiddle.net/vdkdekuu/ and a beautified version:

(function() {

    var g = this,

        h = function(b, d) {

            var a = b.split(.),

                c = g;

            a[0] in c || !c.execScript || c.execScript(var  + a[0]);

            for (var e; a.length && (e = a.shift());) a.length || void 0 === d ? c[e] ? c = c[e] : c = c[e] = {} : c[e] = d

        };

    var l = function(b) {

        var d = b.length;

        if (0 < d) {

            for (var a = Array(d), c = 0; c < d; c++) a[c] = b[c];

            return a

        }

        return []

    };

    var m = function(b) {

        var d = window;

        if (d.addEventListener) d.addEventListener(load, b, !1);

        else if (d.attachEvent) d.attachEvent(onload, b);

        else {

            var a = d.onload;

            d.onload = function() {

                b.call(this);

                a && a.call(this)

            }

        }

    };

    var n, p = function(b, d, a, c, e) {

            this.f = b;

            this.h = d;

            this.i = a;

            this.c = e;

            this.e = {

                height: window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight,

                width: window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth

            };

            this.g = c;

            this.b = {};

            this.a = [];

            this.d = {}

        },

        q = function(b, d) {

            var a, c, e = d.getAttribute(pagespeed_url_hash);

            if (a = e && !(e in b.d))

                if (0 >= d.offsetWidth && 0 >= d.offsetHeight) a = !1;

                else {

                    c = d.getBoundingClientRect();

                    var f = document.body;

                    a = c.top + (pageYOffset in window ? window.pageYOffset : (document.documentElement || f.parentNode || f).scrollTop);

                    c = c.left + (pageXOffset in window ? window.pageXOffset : (document.documentElement || f.parentNode || f).scrollLeft);

                    f = a.toString() + , + c;

                    b.b.hasOwnProperty(f) ? a = !1 : (b.b[f] = !0, a = a <= b.e.height && c <= b.e.width)

                }

            a && (b.a.push(e), b.d[e] = !0)

        };

    p.prototype.checkImageForCriticality = function(b) {

        b.getBoundingClientRect && q(this, b)

    };

    h(pagespeed.CriticalImages.checkImageForCriticality, function(b) {

        n.checkImageForCriticality(b)

    });

    h(pagespeed.CriticalImages.checkCriticalImages, function() {

        r(n)

    });

    var r = function(b) {

            b.b = {};

            for (var d = [IMG, INPUT], a = [], c = 0; c < d.length; ++c) a = a.concat(l(document.getElementsByTagName(d[c])));

            if (0 != a.length && a[0].getBoundingClientRect) {

                for (c = 0; d = a[c]; ++c) q(b, d);

                a = oh= + b.i;

                b.c && (a += &n= + b.c);

                if (d = 0 != b.a.length)

                    for (a += &ci= + encodeURIComponent(b.a[0]), c = 1; c < b.a.length; ++c) {

                        var e = , + encodeURIComponent(b.a[c]);

                        131072 >= a.length + e.length && (a += e)

                    }

                b.g && (e = &rd= + encodeURIComponent(JSON.stringify(s())), 131072 >= a.length + e.length && (a += e), d = !0);

                t = a;

                if (d) {

                    c = b.f;

                    b = b.h;

                    var f;

                    if (window.XMLHttpRequest) f = new XMLHttpRequest;

                    else if (window.ActiveXObject) try {

                        f = new ActiveXObject(Msxml2.XMLHTTP)

                    } catch (k) {

                        try {

                            f = new ActiveXObject(Microsoft.XMLHTTP)

                        } catch (u) {}

                    }

                    f && (f.open(POST, c + (-1 == c.indexOf(?) ? ? : &) + url= + encodeURIComponent(b)), f.setRequestHeader(Content-Type, application/x-www-form-urlencoded), f.send(a))

                }

            }

        },

        s = function() {

            var b = {},

                d = document.getElementsByTagName(IMG);

            if (0 == d.length) return {};

            var a = d[0];

            if (!(naturalWidth in a && naturalHeight in a)) return {};

            for (var c = 0; a = d[c]; ++c) {

                var e = a.getAttribute(pagespeed_url_hash);

                e && (!(e in b) && 0 < a.width && 0 < a.height && 0 < a.naturalWidth && 0 < a.naturalHeight || e in b && a.width >= b[e].k && a.height >= b[e].j) && (b[e] = {

                    rw: a.width,

                    rh: a.height,

                    ow: a.naturalWidth,

                    oh: a.naturalHeight

                })

            }

            return b

        },

        t = ;

    h(pagespeed.CriticalImages.getBeaconData, function() {

        return t

    });

    h(pagespeed.CriticalImages.Run, function(b, d, a, c, e, f) {

        var k = new p(b, d, a, e, f);

        n = k;

        c && m(function() {

            window.setTimeout(function() {

                r(k)

            }, 0)

        })

    });

})();

pagespeed.CriticalImages.Run('/mod_pagespeed_beacon', 'http://www.example.com/slug', 'SLoDkQnME-', true, false, 'gxYRJPh80JY');