Sending Redraw event on_draw does not work on Windows

[Roope Salmi]

state.insert_event(Event::new(WindowEvent::Redraw).direct(Entity::root()));

is intended to cause a new redraw immediately, and in fact does so on Linux.

However, it does not work on Windows.

Workaround: Use a perpetual animation. Ugly, especially given there's no loop functionality yet.