Thiago rightfully reported that my patch from http://trac.webkit.org/changeset/138574 may cause regressions (deadlocks) because it is allocating memory in the fork. There was a commenting explaining that we should not do that but I missed it (sorry).
Created attachment 180953 [details] Patch
Comment on attachment 180953 [details] Patch Clearing flags on attachment: 180953 Committed r138597: <http://trac.webkit.org/changeset/138597>
All reviewed patches have been landed. Closing bug.