<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<script>

function boom()
{
  var frame = document.getElementById("f");
  var frameWin = frame.contentWindow;
  frameWin.VTTCue;
  document.body.removeChild(frame);
  new frameWin.VTTCue(0, 1, "Bug 894104").getCueAsHTML();
}

</script>
</head>

<body onload="boom();"><iframe id="f" src="data:text/html,1"></iframe></body>
</html>
