~jaro/balkon

ref: 8b8b095a2d7cc321b520b3d3dc707f3f0501d2e3 balkon/.golden/richParagraphLayout d---------
Describe box edges with extensible type.
Test interaction between boxes and mixed script.
Test line breaking in boxes.
Handle ancestor boxes in rich layout.
Add ancestor boxes to interface.
Test layout with mixed font sizes.
Test Rich line wrapping.
Test Rich layout.