PASS: host child combinator add stays on the host-side tree (3 invalidations)
PASS: host descendant combinator add stays on the host-side tree (4 invalidations)
PASS: broad host-side stylesheet add avoids document-wide invalidation (3 invalidations)
PASS: broad host-side sibling escape reaches root-side invalidation (1 full invalidations)
PASS: broad functional host-side selector avoids document-wide invalidation (3 invalidations)
PASS: broad functional host-side sibling escape reaches root-side invalidation (1 full invalidations)