In order to be able to put the renderer on a subpixel position off of the owning graphics layer.
Created attachment 224410 [details] Patch
this patch has dependencies on bug 128911. won't build at this point.
Created attachment 224415 [details] Patch
Comment on attachment 224415 [details] Patch Clearing flags on attachment: 224415 Committed r164415: <http://trac.webkit.org/changeset/164415>
All reviewed patches have been landed. Closing bug.