LayoutTests/http/tests/security/mixedContent/resources/frame-with-redirect-https-to-http-image-secure-cookie-block.html

<script>
var frameDidLoad = false;
document.cookie = "secureCookie=yes;secure";
if (window.testRunner)
    internals.settings.setAllowRunningOfInsecureContent(true);
onload = function()
{
    console.log(document.cookie);
    if (window.opener)
        window.opener.postMessage(frameDidLoad ? 'done' : 'blocked', '*');
}
</script>
<img onload="window.frameDidLoad = true" src="https://127.0.0.1:8443/resources/redirect.php?url=http://127.0.0.1:8080/security/resources/compass.jpg">