An opaque type that tracks a #CoglOnscreenResizeCallback and
associated user data. A #CoglOnscreenResizeClosure pointer will be
returned from cogl_onscreen_add_resize_callback() and it allows you
to remove a callback later using
cogl_onscreen_remove_resize_callback().
An opaque type that tracks a #CoglOnscreenResizeCallback and associated user data. A #CoglOnscreenResizeClosure pointer will be returned from cogl_onscreen_add_resize_callback() and it allows you to remove a callback later using cogl_onscreen_remove_resize_callback().