MPTT doesn't always work when creating tree at once
When creating a tree with one create call (one2many filled). The resulted MPTT is not always correct because _update_tree is called on the child when it was not yet called on the parent.
When creating a tree with one create call (one2many filled). The resulted MPTT is not always correct because _update_tree is called on the child when it was not yet called on the parent.