CSSParser should return ImmutableStylePropertySets.
Created attachment 197996 [details] Patch
Comment on attachment 197996 [details] Patch Attachment 197996 [details] did not pass efl-ews (efl): Output: http://webkit-queues.appspot.com/results/51066
Comment on attachment 197996 [details] Patch Attachment 197996 [details] did not pass qt-ews (qt): Output: http://webkit-queues.appspot.com/results/140167
Comment on attachment 197996 [details] Patch Attachment 197996 [details] did not pass qt-wk2-ews (qt): Output: http://webkit-queues.appspot.com/results/151238
Created attachment 197998 [details] Patch
Committed r148399: <http://trac.webkit.org/changeset/148399>