Move some processing code from wxMenuItemAction to CocoaItemSelected. Add Cocoa_validateMenuItem and use it instead of calling IsEnabled directly. Do not set the target or action for wxMenuItem that open submenus. git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@29865 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775