Otherwise we'll have confused dependency graph builder, which wouldn't be able to
build proper graph.
Didn't find a way to avoid world copy here, we can probably escape with some shallow
copy here, but that will currently complicate code a lot.
Ideas to consider here:
- Use shallow copy of existing world after new ID management API is in place.
Downside would be thread safety, kind of nice to have everything local.
- Switch depsgraph away from ID_TAG and do hash lookup or so.
This will slow down depsgraph builder, but will make code more reliable.