Simplified loading of the SLA support structures into the scene.

Fixed referesh of SLA support structures after Undo / Redo
and when moving an object outside / inside the build volume.

src/slic3r/GUI/GLCanvas3D.hpp

@@ -730,8 +730,6 @@ private:
     void _load_gcode_unretractions(const GCodePreviewData& preview_data);
     // generates objects and wipe tower geometry
     void _load_fff_shells();
-    // generates objects geometry for sla
-    void _load_sla_shells();
     // sets gcode geometry visibility according to user selection
     void _update_gcode_volumes_visibility(const GCodePreviewData& preview_data);
     void _update_toolpath_volumes_outside_state();