chromium/third_party/blink/web_tests/gamepad/multiple-event-listeners.html

<!DOCTYPE html>
<html>
<body>
<script src="../resources/js-test.js"></script>
<script>
description("Test that when there are multiple gamepad event listeners and one is getting removed the others still receive events.");
window.jsTestIsAsync = true;

if (!window.gamepadController) {
    debug("This test cannot work without gamepadController.");
}

var listenerToRemove = window.addEventListener('gamepadconnected', function() {});
window.addEventListener('gamepadconnected', function() {
    testPassed("gamepadconnected event received");
    finishJSTest();
});
window.removeEventListener('gamepadconnected', listenerToRemove);

setTimeout(function() {
    testFailed("gamepadconnected event should have been received.");
    finishJSTest();
}, 100);

if (gamepadController) {
    gamepadController.connect(0);
    gamepadController.dispatchConnected(0);
}

</script>
</html>