Viewport <#document> at (0,0) content-size 800x600 children: not-inline
  BlockContainer <html> at (0,0) content-size 800x16 [BFC] children: not-inline
    BlockContainer <body> at (8,8) content-size 784x0 children: not-inline
      BlockContainer <div#foo> at (0,0) content-size 123x456 positioned [BFC] children: not-inline

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x16]
    PaintableWithLines (BlockContainer<BODY>) [8,8 784x0]
      PaintableWithLines (BlockContainer<DIV>#foo) [0,0 123x456]
