Patch landed in r97438 uses inconsistently both flattening and flattering (PROP_ENABLE_FRAME_FLATTERING) and giving a wild shot I guess the variant with 'r' is wrong.
Thanks for catch that. Flattening is indeed the correct spelling.
Created attachment 110993 [details] Property name correction. Thanks for this catch. Attached is the patch to correct the spelling as 'FLATTENING'.
Comment on attachment 110993 [details] Property name correction. Clearing flags on attachment: 110993 Committed r97474: <http://trac.webkit.org/changeset/97474>
All reviewed patches have been landed. Closing bug.