Map window/its decoration *after* calling render_layout()

Thus, no more flickering because the window was first mapped and then
moved. Especially users of multiple monitors should be happy now ;-).
Rather radical change, though, so be prepared for problems.

src/layout.c

@@ -282,9 +282,6 @@ void render_container(xcb_connection_t *conn, Container *container) {
         Client *client;
         int num_clients = 0, current_client = 0;
 
-        if (container->currently_focused == NULL)
-                return;
-
         CIRCLEQ_FOREACH(client, &(container->clients), clients)
                 num_clients++;