As of r156861, Coordinated Graphics does not use DrawingAreaProxyImpl. So, Coordinated Graphics bits should be removed from DrawingAreaProxyImpl.
Created attachment 215237 [details] Patch
Comment on attachment 215237 [details] Patch Clearing flags on attachment: 215237 Committed r158084: <http://trac.webkit.org/changeset/158084>
All reviewed patches have been landed. Closing bug.