In ScrollbarThemeMac, supportsExpandedScrollbars() checked if NSScrollerImp responds to isExpanded. The result of this function is used to determine whether or not is it safe to call setExpanded. We should just check for setExpanded instead. <rdar://problem/11065691>
Created attachment 139678 [details] Patch
Thanks Anders! http://trac.webkit.org/changeset/115823
This patch was wrong! The selector is setExpanded: with the colon, not setExpanded without a colon!
Oops!
(In reply to comment #3) > This patch was wrong! The selector is setExpanded: with the colon, not setExpanded without a colon! Thanks for noticing that! Added the colon here: http://trac.webkit.org/changeset/115868