Viewport <#document> at (0,0) content-size 800x600 children: not-inline
  BlockContainer <html> at (0,0) content-size 800x54 [BFC] children: not-inline
    BlockContainer <body> at (8,8) content-size 784x38 children: not-inline
      BlockContainer <div.hmm> at (18,18) content-size 764x18 children: inline
        frag 0 from TextNode start: 0, length: 5, rect: [18,18 36.84375x18] baseline: 13.796875
            "hello"
        TextNode <#text>

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x54]
    PaintableWithLines (BlockContainer<BODY>) [8,8 784x38]
      PaintableWithLines (BlockContainer<DIV>.hmm) [8,8 784x38]
        TextPaintable (TextNode<#text>)
