It only checks if the string content is qualified for simple font path. It does not check all the other related properties.
<rdar://problem/30367302>
Created attachment 300663 [details] Patch
Comment on attachment 300663 [details] Patch Clearing flags on attachment: 300663 Committed r211682: <http://trac.webkit.org/changeset/211682>
All reviewed patches have been landed. Closing bug.