Fix missed handling of a irc:// url cmdl arg on app start
Application::handleActivate() handles the arguments passed from the signal KDBusService::activateRequested. The API dox of the signal tells: " The arguments the executable was called with, starting with the executable file name. See QCoreApplication::arguments(). This can also be empty. " 267e3762 tried to handle the case of no args passed, which though created bug 374690, which then got treated by 2605c61f, which then created bug 391698.
Hopefully we end the chain here :)
Tested with starting konversation by konversation irc://chat.freenode.net/kde-devel, then leaving the channel, then calling xdg-open irc://chat.freenode.net/kde-devel.