<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" onload="runTest()">
  <defs>
    <path d="M150 50 L 450 50" />
  </defs>
  <text>
    <textPath id="theTP" xlink:href="#foo">FAIL</textPath>
  </text>
  <script><![CDATA[
    function runTest() {
      var path = document.getElementsByTagName("path")[0];
      path.parentNode.addEventListener('DOMSubtreeModified', handler);
      path.setAttribute("id","foo");
      if (window.testRunner)
        testRunner.notifyDone();
    }
  ]]></script>
</svg>