Function compute_damage_and_rebuild_box_tree 

pub(crate) fn compute_damage_and_rebuild_box_tree(
    box_tree: &mut Option<Arc<BoxTree>>,
    layout_context: &LayoutContext<'_>,
    dirty_root: ServoLayoutNode<'_>,
    root_node: ServoLayoutNode<'_>,
    damage_from_environment: RestyleDamage,
) -> RestyleDamage