<!DOCTYPE html>
<script>
var request = window.indexedDB.open("TestIndexedDB");
request.onsuccess = () => {
    window.webkit.messageHandlers.testHandler.postMessage("Open Succeeded");
    var db = event.target.result;
    db.onversionchange = () => {
        window.webkit.messageHandlers.testHandler.postMessage("Version Change");
    }
}
request.onerror = () => {
    window.webkit.messageHandlers.testHandler.postMessage("Open Failed: " + request.error);
}
</script>