OSX specific : Set top border for the mode buttons, when settings pages has new layouts

(when tabs bar is hidden)

+ Code cleaning for OG_CustomCtrl (delete unused input parameter from the draw_blinking_bmp())

src/slic3r/GUI/Plater.hpp

@@ -72,6 +72,7 @@ public:
     void update_all_preset_comboboxes();
     void update_presets(Slic3r::Preset::Type preset_type);
     void update_mode_sizer() const;
+    void change_top_border_for_mode_sizer(bool increase_border);
     void update_reslice_btn_tooltip() const;
     void msw_rescale();
     void sys_color_changed();