A workaround fix for Alt+TAB picking up wrong window when used on a application group. The check for Quirk::ACTIVE is not valid right now due to the fact we're making the switcher window active prior to display (this is done this way to fix some other bugs). So a workaround is to save the last active window prior to this action and use this during the checks. It fixes a very annoying bug.. Fixes: https://bugs.launchpad.net/bugs/1071298. Approved by Andrea Azzarone, Thomi Richards.