iframe フォームで Account Engagement トラッキングコードを先に読み込むようにする

<script type="text/javascript">
piAId = '112233';
piCId = '123';
(function() {
function async_load(){
var s = document.createElement('script'); s.type = 'text/javascript';
s.src = ('https:' == document.location.protocol ? 'https://pi'; : 'http://cdn';) + '.pardot.com/pd.js';
var c = document.getElementsByTagName('script')[0]; c.parentNode.insertBefore(s, c);
}
if(window.attachEvent) { window.attachEvent('onload', async_load); }
else { window.addEventListener('load', async_load, false); }
})();
</script>

<script type="text/javascript">
piAId = '112233';
piCId = '123';
</script>
​<script type="text/javascript" src="http://cdn.pardot.com/pd.js"></script>