Specific changes:
- flexbox-table-fixup-001a.xhtml previously tested that table parts would get wrapped in an anonymous table, which would form a single flex item. This patch changes it to instead test that each table-part forms its own flex item.
- flexbox-table-fixup-001b.xhtml previously was a "belt and suspenders" afterthought to its "001a" counterpart. It verified that flex-item properties (like "flex") had no effect on table parts in a flex container. This patch removes this test (since it's no longer valid) and renames the "001a" test to simply "001" as a result.
- flexbox-with-pseudo-elements-003.html previously tested that ::before/::after pseudo-elements with table-part display values would have their flex-item-related properties ignored (because they'd be wrapped in an anonymous table). This patch flips that expectation, because now these pseudo-elements will directly become flex items and these properties should be honored.