
in _cogl_material_prune_empty_layer_difference we sometimes unref the given layer before dereferencing it to get a pointer to its parent. This defers the unref until after we have fetched the parent pointer.
in _cogl_material_prune_empty_layer_difference we sometimes unref the given layer before dereferencing it to get a pointer to its parent. This defers the unref until after we have fetched the parent pointer.