Instead of going through wined3d_device_restore_fullscreen_window() /
wined3d_device_setup_fullscreen_window(). The main point of those functions is
changing the window styles, but we don't actually need that here. More
importantly, we filter the messages generated by those functions in wined3d,
while tests show that messages generated by SetDisplayMode() /
RestoreDisplayMode() are visible to the application. Applications depend on
WM_SIZE in particular.