title: How to trigger a window.scrollTo(x, y) in phantomJS
body: <p>I open a web page, and I want trigger a scrolling in onLoadFinished callback.
  but it dose't working. I also tried scrollPosition and set timer to sent key event.
  Both of them dose't working.
  So ask for help.</p>
  
  <pre><code>page.onLoadFinished = function() {
      window.scrollTo(0, document.height);
  }
  
  page.open('http://www.XXX.com', function (status) {
      if (status !== 'success') {
          console.log('Unable to open weibo.com');
      }
  }
  </code></pre>