title: Query for Google Analaytics pixel with JavaScript
body: <p>When Google Analytics Js is added to a page, it generates a gif pixel looking like:</p>
  
  <pre><code>http://www.google-analytics.com/__utm.gif?utmwv=9.9.9&amp;utms=9&amp;utmn=1234567890&amp;utmhn=google.com&amp;utmcs=UTF-8&amp;utmsr=320X480&amp;utmvp=320X480&amp;utmsc=9000bits&amp;utmul=en-us&amp;utmje=9&amp;utmfl=-&amp;utmdt=Google&amp;utmhid=1234567890&amp;utmr=-&amp;utmp=%2F&amp;utmht=1234567890&amp;utmac=UA-123456789-0&amp;utmcc=sample&amp;utmu=sample
  </code></pre>
  
  <p>I'm trying to write a functional test checking for the existence of this pixel on the page. BUt it appears this pixel is not added to the DOM so I've not been able to grab it with with either pure JavaScript:</p>
  
  <pre><code>document.querySelectorAll("img")
  </code></pre>
  
  <p>or jQuery:</p>
  
  <pre><code>jQuery("img")
  </code></pre>
  
  <p>I also don't find the pixel when viewing the page's HTML source (Hit keyboards combination Ctrl - U or Command - U).</p>
  
  <p>Do you have some suggestions for me on how to grab it? Or a better way to check for the existence of Google Analytics on page (in terms of automatic / functional tests)?</p>