<!DOCTYPE html>
<body>
<canvas id="canvas"></canvas>
<script>
// Used by image-tainting-in-cross-origin-iframe.sub.html to check that an
// image resource loaded by the top level frame that is same-origin to the
// frame isn't treated as a same-origin resource in a cross-origin iframe.
const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');
const img = new Image();
img.src = 'http://{{host}}:{{ports[http][0]}}/images/blue-png-cachable.py';
img.onload = () => {
  ctx.drawImage(img, 0, 0);
  try {
    ctx.getImageData(0, 0, 1, 1);
    parent.postMessage('FAIL: getImageData() didn\'t throw', '*');
  } catch (e) {
    parent.postMessage('DONE', '*');
  }
};
</script>
</body>
