WebKitGtk exposes all tables (data and layout) as tables, overriding WebCore Accessibility's default behavior in order to do so. The main motivation behind this platform difference was to make it possible for Orca to be able to provide consistent user experiences between Gecko and WebKitGtk. Given improved table identification heuristics in both engines, Orca now treats tables exposed with layout-guess:true as non-tables. Since Orca is deferring to the decision of WebKit, there doesn't seem to be much benefit in continuing to override WebCore Accessibility's default behavior in WebKitGtk.
<rdar://problem/20911379>
Created attachment 252935 [details] Patch
BTW, I just opened bug 144898 for the EFL port. I'm pretty sure they just inherited the GTK port's expectation wrt table exposure. But I could be wrong, and I cannot build WebKitEfl at the moment even if I were sure I was right. So we need one of those developers to chime in.
Comment on attachment 252935 [details] Patch Clearing flags on attachment: 252935 Committed r184199: <http://trac.webkit.org/changeset/184199>
All reviewed patches have been landed. Closing bug.