@Override
    public Iterator<T> iterator() {
        return new ThreadRobustIterator<>(items);
    }
<p>Returns an iterator over the items in this list. As opposed to <code>CopyOnWriteArrayList</code>, this iterator
may see items added to the <code>ThreadRobustList</code> even if they occur <em>after</em> a call to this method.</p>
<p>The returned iterator does not support <code>remove()</code>.</p>

@return an iterator over this list
vespajlib/src/main/java/com/yahoo/yolean/concurrent/ThreadRobustList.java