LayoutTests/http/tests/site-isolation/basic-iframe-render-output-expected.txt

layer at (0,0) size 800x600
  RenderView at (0,0) size 800x600
layer at (0,0) size 800x600
  RenderBlock {HTML} at (0,0) size 800x600
    RenderBody {BODY} at (8,8) size 784x584 [bgcolor=#0000FF]
      RenderText {#text} at (0,0) size 0x0
layer at (8,8) size 300x150
  RenderIFrame {IFRAME} at (0,0) size 300x150
    layer at (0,0) size 300x150
      RenderView at (0,0) size 300x150
    layer at (0,0) size 300x150
      RenderBlock {HTML} at (0,0) size 300x150
        RenderBody {BODY} at (8,8) size 284x134 [bgcolor=#008000]