In the attached file the orange div should overflow both regions (or at least the second region). Toggle the transform on the region to see how it should render.
Created attachment 202991 [details] Test-case
Created attachment 203531 [details] Test-case
Still repros on today's nightly (r151543)
Created attachment 229645 [details] Test Problem was fixed by the new visual overflow implementation, this patch just adds test for it.
Comment on attachment 229645 [details] Test r=me
Comment on attachment 229645 [details] Test Clearing flags on attachment: 229645 Committed r167492: <http://trac.webkit.org/changeset/167492>
All reviewed patches have been landed. Closing bug.