Inset box-shadows are currently painting by applying generic shadow blur to the entire rect instead of using the optimized tiled shadow blur.
This affects common pastebin sites that has a inset box-shadows around the entire shown paste.
Created attachment 192011 [details]
Created attachment 192012 [details]
Created attachment 192243 [details]
Avoid copying fill-color by just calling clearShadow later
Committed r145366: <http://trac.webkit.org/changeset/145366>