OpenGL: Layering breaks culling

It seems that the winding order gets reversed with layering.

For example, a `ShaderEffect` that has `cullMode: ShaderEffect.BackFaceCulling` is not displayed if it is a child of a layered item (does not need to be a direct child). In that case, culling the front face does the job, even the item is not rotated to show its back face, so I assume it is a winding order issue.

This does not seem to be a problem with Vulkan.