<!DOCTYPE html>
<script>
onload=function(){
  var img = new Image();
  img.src = "http://example.com/tests/dom/serviceworkers/test/fetch/hsts/image-20px.png";
  img.onload = function() {
    window.parent.postMessage({status: "image", data: img.width}, "*");
  };
  img.onerror = function() {
    window.parent.postMessage({status: "image", data: "error"}, "*");
  };
};
</script>
