spicec: Fix info layer sometimes not showing

Currently we are calling show_info_layer from hide_gui in application.cpp, but
there are 2 cases where this does not happen:

1) When compiled without gui support hide_gui is a complete nop, so we never
   show the info layer when compiled without gui support
2) When run with --controller we never show the gui, and hide_gui
   checks if there is a gui to hide as the first thing and if not returns
   resulting in show_info_layer not being called, and thus the info layer
   not showing when launched from the xpi

This patch fixes both by adding a call to show_info_layer from
on_visibility_start note that on_visibility_start also calls hide_gui,
so in some cases show_info_layer may be called twice, this is not a
problem as show_info_layer is protected against this.

client/application.cpp

@@ -854,6 +854,7 @@ void Application::on_visibility_start(int screen_id)
     }
     set_state(VISIBILITY);
     hide_gui();
+    show_info_layer();
 }
 
 void Application::on_disconnecting()