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chromium/third_party/blink/web_tests/images/script-tests/TEMPLATE.html 

<!DOCTYPE html">
<title>Add description of test here.</title>
<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<script>
async_test(function(t) {
    // Write your test code here.
    t.done();
});
</script>