When WebPagePrivate is being destroyed, m_mainFrame could be a null pointer.
Created attachment 169772 [details] Patch
Comment on attachment 169772 [details] Patch Merge error - clearly flags.
Created attachment 169773 [details] Patch
Comment on attachment 169773 [details] Patch Clearing flags on attachment: 169773 Committed r131992: <http://trac.webkit.org/changeset/131992>
All reviewed patches have been landed. Closing bug.