Order window: Add button to toggle order management button

src/lang/english.txt

@@ -5528,6 +5528,7 @@ STR_REFIT_AIRCRAFT_REFIT_TOOLTIP                                :{BLACK}Refit ai
 STR_ORDERS_CAPTION                                              :{WHITE}{VEHICLE} (Orders)
 STR_ORDERS_TIMETABLE_VIEW                                       :{BLACK}Timetable
 STR_ORDERS_TIMETABLE_VIEW_TOOLTIP                               :{BLACK}Switch to the timetable view
+STR_ORDERS_TOGGLE_MANAGEMENT_BUTTON_TOOLTIP                     :{BLACK}Toggle showing order management button
 
 STR_ORDERS_LIST_TOOLTIP                                         :{BLACK}Order list - click on an order to highlight it. Ctrl+Click scrolls to the order's destination
 STR_ORDER_INDEX                                                 :{COMMA}:{NBSP}

src/order_gui.cpp

@@ -2916,6 +2916,12 @@ public:
 				ShowQueryString(STR_JUST_INT, STR_TRACE_RESTRICT_VALUE_CAPTION, 10, this, CS_NUMERAL, QSF_NONE);
 				break;
 			}
+
+			case WID_O_TOGGLE_SIZE: {
+				_settings_client.gui.show_order_management_button = !_settings_client.gui.show_order_management_button;
+				InvalidateWindowClassesData(WC_VEHICLE_ORDERS);
+				break;
+			}
 		}
 	}
 
@@ -3294,6 +3300,7 @@ static const NWidgetPart _nested_orders_train_widgets[] = {
 		NWidget(WWT_CLOSEBOX, COLOUR_GREY),
 		NWidget(WWT_CAPTION, COLOUR_GREY, WID_O_CAPTION), SetDataTip(STR_ORDERS_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
 		NWidget(WWT_PUSHBTN, COLOUR_GREY, WID_O_TIMETABLE_VIEW), SetMinimalSize(61, 14), SetDataTip(0x0, STR_ORDERS_TIMETABLE_VIEW_TOOLTIP),
+		NWidget(WWT_IMGBTN, COLOUR_GREY, WID_O_TOGGLE_SIZE), SetDataTip(SPR_LARGE_SMALL_WINDOW, STR_ORDERS_TOGGLE_MANAGEMENT_BUTTON_TOOLTIP),
 		NWidget(WWT_SHADEBOX, COLOUR_GREY),
 		NWidget(WWT_DEFSIZEBOX, COLOUR_GREY),
 		NWidget(WWT_STICKYBOX, COLOUR_GREY),
@@ -3430,6 +3437,7 @@ static const NWidgetPart _nested_orders_widgets[] = {
 		NWidget(WWT_CLOSEBOX, COLOUR_GREY),
 		NWidget(WWT_CAPTION, COLOUR_GREY, WID_O_CAPTION), SetDataTip(STR_ORDERS_CAPTION, STR_TOOLTIP_WINDOW_TITLE_DRAG_THIS),
 		NWidget(WWT_PUSHBTN, COLOUR_GREY, WID_O_TIMETABLE_VIEW), SetMinimalSize(61, 14), SetDataTip(0x0, STR_ORDERS_TIMETABLE_VIEW_TOOLTIP),
+		NWidget(WWT_IMGBTN, COLOUR_GREY, WID_O_TOGGLE_SIZE), SetDataTip(SPR_LARGE_SMALL_WINDOW, STR_ORDERS_TOGGLE_MANAGEMENT_BUTTON_TOOLTIP),
 		NWidget(WWT_SHADEBOX, COLOUR_GREY),
 		NWidget(WWT_DEFSIZEBOX, COLOUR_GREY),
 		NWidget(WWT_STICKYBOX, COLOUR_GREY),

src/widgets/order_widget.h

@@ -66,6 +66,7 @@ enum OrderWidgets {
 	WID_O_SEL_OCCUPANCY,             ///< #NWID_SELECTION widget for the occupancy list panel.
 	WID_O_OCCUPANCY_LIST,            ///< Occupancy list panel.
 	WID_O_OCCUPANCY_TOGGLE,          ///< Toggle display of occupancy measures.
+	WID_O_TOGGLE_SIZE,               ///< Toggle show order management button.
 };
 
 /** Widgets of the #CargoTypeOrdersWindow class. */