<!DOCTYPE html>
<html>
  <body onload="loaded()">
    <div style="position: relative; top: 100px; overflow: scroll; width: 100px; height: 100px;">
      <div style="height: 200px">foo</div></div>
    <script>
      function loaded() {
        var insPoint = document.querySelector("div");
        insPoint.scrollTop = 50;
        var div = document.createElement("div");
        div.style.position = "absolute";
        div.style.top = '50px';
        div.appendChild(document.createTextNode("abs"));
        insPoint.insertBefore(div, insPoint.firstChild);
      }
    </script>
  </body>
</html>