init-message-event-isolated-world.html

<!DOCTYPE html>
<p>Tests that properties of MessageEvents initialized with initMessageEvent() are cloned when accessed in isolated worlds.</p>
<div id="main"></div>
<div id="isolated"></div>
<script>
testRunner.dumpAsText();

function addListener(worldType) {
    document.getElementById(worldType).addEventListener("MessageEvent", function(event) {
        console.log("MessageEvent received in " + worldType + " world");
        console.log("detail was " + JSON.stringify(event.data));
    });
}

function sendCloneableObject(targetWorldType) {
    var newEvent = document.createEvent("MessageEvent");
    newEvent.initMessageEvent("MessageEvent", false, false, { foo: 5, bar: 'hello', targetWorld: targetWorldType });
    document.getElementById(targetWorldType).dispatchEvent(newEvent);
}

var sendScript = "(" + sendCloneableObject.toString() + ")('main');";
addListener("main");
testRunner.evaluateScriptInIsolatedWorld(1, sendScript);
var receiveScript = "(" + addListener.toString() + ")('isolated');";
testRunner.evaluateScriptInIsolatedWorld(1, receiveScript);
sendCloneableObject("isolated");
</script>

chromium/third_party/blink/web_tests/fast/events/init-message-event-isolated-world.html