eliminate unnecessary uses of octave_qobject in GUI classes * BaseControl.cc, BaseControl.h, ButtonControl.cc, ButtonControl.h, ButtonGroup.cc, ButtonGroup.h, Canvas.cc, Canvas.h, CheckBoxControl.cc, CheckBoxControl.h, Container.cc, Container.h, ContextMenu.cc, ContextMenu.h, EditControl.cc, EditControl.h, Figure.cc, Figure.h, GLCanvas.cc, GLCanvas.h, ListBoxControl.cc, ListBoxControl.h, Menu.cc, Menu.h, Object.cc, Object.h, Panel.cc, Panel.h, PopupMenuControl.cc, PopupMenuControl.h, PushButtonControl.cc, PushButtonControl.h, PushTool.cc, PushTool.h, RadioButtonControl.cc, RadioButtonControl.h, SliderControl.cc, SliderControl.h, Table.cc, Table.h, TextControl.cc, TextControl.h, ToggleButtonControl.cc, ToggleButtonControl.h, ToggleTool.cc, ToggleTool.h, ToolBar.cc, ToolBar.h, ToolBarButton.cc, ToolBarButton.h, annotation-dialog.cc, annotation-dialog.h, qt-graphics-toolkit.cc, qt-graphics-toolkit.h, command-widget.h, community-news.cc, community-news.h, documentation-bookmarks.cc, documentation-bookmarks.h, documentation.cc, external-editor-interface.cc, external-editor-interface.h, find-files-dialog.cc, find-files-dialog.h, graphics-init.cc, graphics-init.h, interpreter-qobject.cc, file-editor.cc, find-dialog.cc, find-dialog.h, main-window.cc, main-window.h, news-reader.cc, news-reader.h, octave-qobject.cc, release-notes.cc, resource-manager.cc, set-path-dialog.cc, set-path-dialog.h, shortcut-manager.cc, shortcut-manager.h, welcome-wizard.cc, welcome-wizard.h, workspace-model.cc: Don't store references to octave_qobject in GUI classes where it is no longer needed. Eliminate unnecessary octave_qobject constructor arguments. Change all uses.

--- a/libgui/graphics/ContextMenu.cc	Sun Dec 04 22:56:23 2022 -0500
+++ b/libgui/graphics/ContextMenu.cc	Sun Dec 04 22:57:02 2022 -0500
@@ -33,16 +33,13 @@
 #include "QtHandlesUtils.h"
 #include "qt-graphics-toolkit.h"
 
-#include "octave-qobject.h"
-
 #include "interpreter.h"
 
 namespace octave
 {
 
   ContextMenu *
-  ContextMenu::create (octave::base_qobject& oct_qobj,
-                       octave::interpreter& interp, const graphics_object& go)
+  ContextMenu::create (octave::interpreter& interp, const graphics_object& go)
   {
     Object *xparent = parentObject (interp, go);
 
@@ -50,16 +47,15 @@
       {
         QWidget *w = xparent->qWidget<QWidget> ();
 
-        return new ContextMenu (oct_qobj, interp, go, new QMenu (w));
+        return new ContextMenu (interp, go, new QMenu (w));
       }
 
     return nullptr;
   }
 
-  ContextMenu::ContextMenu (octave::base_qobject& oct_qobj,
-                            octave::interpreter& interp,
+  ContextMenu::ContextMenu (octave::interpreter& interp,
                             const graphics_object& go, QMenu *xmenu)
-    : Object (oct_qobj, interp, go, xmenu)
+    : Object (interp, go, xmenu)
   {
     xmenu->setAutoFillBackground (true);