Storing layout parameters on the RenderMathMLRoot class may cause update issues (e.g. when zooming in/out). This is actually not really needed since reading the parameters from the MATH table is not too expensive and most of them are only used during layoutBlock. We separate horizontal and vertical parameters since the latter are not need for preferred width calculations.
Created attachment 286846 [details]
Committed r204956: <http://trac.webkit.org/changeset/204956>