This is related to bug 5255. The shadow color alpha must be multiplied by the context brush alpha.
(In reply to comment #0) > This is related to bug 5255. I meant 52559.
Created attachment 79244 [details] Patch
Comment on attachment 79244 [details] Patch Clearing flags on attachment: 79244 Committed r76033: <http://trac.webkit.org/changeset/76033>
All reviewed patches have been landed. Closing bug.