GlyphBufferAdvance is not necessaryly conversible to FloatSize. Also, this code was doing extra work by transforming height value.
Created attachment 269760 [details]
Created attachment 269761 [details]
Comment on attachment 269761 [details]
Clearing flags on attachment: 269761
Committed r195596: <http://trac.webkit.org/changeset/195596>
All reviewed patches have been landed. Closing bug.