Viewport <#document> at (0,0) content-size 800x600 children: not-inline
  BlockContainer <html> at (0,0) content-size 800x17 [BFC] children: inline
    InlineNode <span>
      frag 0 from TextNode start: 0, length: 7, rect: [0,0 51.75x17] baseline: 13.296875
          "whf :^)"
      TextNode <#text>

ViewportPaintable (Viewport<#document>) [0,0 800x600]
  PaintableWithLines (BlockContainer<HTML>) [0,0 800x17]
    PaintableWithLines (InlineNode<SPAN>)
      TextPaintable (TextNode<#text>)
