PluginController::isPluginVisible() was introduced by http://webkit.org/b/60285. This method had been used only for WebKit2 on Windows, and no one uses it now. So we can remove it.
Created attachment 250925 [details] Patch
LGTM, but I let WK2 owners to do the final review.
Comment on attachment 250925 [details] Patch Clearing flags on attachment: 250925 Committed r182892: <http://trac.webkit.org/changeset/182892>
All reviewed patches have been landed. Closing bug.