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<!DOCTYPE HTML>
<meta charset=utf-8>
<title>Element Timing: observe cross-origin images but without renderTime</title>
<body>
<style>
body {
margin: 0;
}
</style>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/element-timing-helpers.js"></script>
<script>
async_test((t) => {
const test_start = performance.now();
assert_implements(window.PerformanceElementTiming, "PerformanceElementTiming is not implemented");
let img;
const pathname = 'http://{{domains[www]}}:{{ports[http][1]}}'
+ '/element-timing/resources/square100.png';
const observer = new PerformanceObserver(
t.step_func_done((entryList) => {
assert_equals(entryList.getEntries().length, 1);
const entry = entryList.getEntries()[0];
checkElement(entry, pathname, 'my_image', 'the_id', test_start, img);
assert_greater_than_equal(entry.renderTime, entry.loadTime,
'The renderTime of a cross-origin image should be coarse but at least as high as loadTime');
checkRect(entry, [0, 100, 0, 100]);
checkNaturalSize(entry, 100, 100);
})
);
observer.observe({entryTypes: ['element']});
// We add the image during onload to be sure that the observer is registered
// in time for it to observe the element timing.
// TODO(npm): change observer to use buffered flag.
window.onload = t.step_func(() => {
// Add a cross origin image resource.
img = document.createElement('img');
img.src = pathname;
img.setAttribute('elementtiming', 'my_image');
img.setAttribute('id', 'the_id');
document.body.appendChild(img);
});
}, 'Cross-origin image element is NOT observable.');
</script>
</body>
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