tdf#130857 qt: Let QtAccessibleWidget subclass QObject

This will allow to pass it in a QVariant, which will
be used to support custom accessible implementations
for QtInstanceDrawingArea in
QtInstanceBuilder::weld_drawing_area in an upcoming
commit.

At least the Qt 5 moc does not process Qt version
checks like

    #if QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)

which would result in failures like

    In file included from /home/michi/development/git/libreoffice/vcl/qt5/QtAccessibleWidget.cxx:21:
    /home/michi/development/git/libreoffice/workdir/CustomTarget/vcl/qt5/QtAccessibleWidget.moc:91:29: error: unknown type name 'QAccessibleAttributesInterface'; did you mean 'QAccessibleActionInterface'?
       91 |         return static_cast< QAccessibleAttributesInterface*>(this);
          |                             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          |                             QAccessibleActionInterface
    /usr/include/x86_64-linux-gnu/qt5/QtGui/qaccessible.h:627:20: note: 'QAccessibleActionInterface' declared here
      627 | class Q_GUI_EXPORT QAccessibleActionInterface
          |                    ^
    In file included from /home/michi/development/git/libreoffice/vcl/qt5/QtAccessibleWidget.cxx:21:
    /home/michi/development/git/libreoffice/workdir/CustomTarget/vcl/qt5/QtAccessibleWidget.moc:97:29: error: unknown type name 'QAccessibleSelectionInterface'; did you mean 'QAccessibleActionInterface'?
       97 |         return static_cast< QAccessibleSelectionInterface*>(this);
          |                             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
          |                             QAccessibleActionInterface
    /usr/include/x86_64-linux-gnu/qt5/QtGui/qaccessible.h:627:20: note: 'QAccessibleActionInterface' declared here
      627 | class Q_GUI_EXPORT QAccessibleActionInterface
          |                    ^
    2 errors generated.

Explicitly exclude the Qt >= 6.x specific
code in the header from the moc run by making it
conditional on

    #ifndef Q_MOC_RUN

to make that work.

Change-Id: I1ea3c37d0041dac89d632970d810ae951ff4afbb
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/184876
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>

vcl/CustomTarget_qt5_moc.mk

@@ -10,6 +10,7 @@
 $(eval $(call gb_CustomTarget_CustomTarget,vcl/qt5))
 
 $(call gb_CustomTarget_get_target,vcl/qt5) : \
+	$(gb_CustomTarget_workdir)/vcl/qt5/QtAccessibleWidget.moc \
 	$(gb_CustomTarget_workdir)/vcl/qt5/QtClipboard.moc \
 	$(gb_CustomTarget_workdir)/vcl/qt5/QtDoubleSpinBox.moc \
 	$(gb_CustomTarget_workdir)/vcl/qt5/QtExpander.moc \

vcl/CustomTarget_qt6_moc.mk

@@ -10,6 +10,7 @@
 $(eval $(call gb_CustomTarget_CustomTarget,vcl/qt6))
 
 $(call gb_CustomTarget_get_target,vcl/qt6) : \
+	$(gb_CustomTarget_workdir)/vcl/qt6/QtAccessibleWidget.moc \
 	$(gb_CustomTarget_workdir)/vcl/qt6/QtClipboard.moc \
 	$(gb_CustomTarget_workdir)/vcl/qt6/QtDoubleSpinBox.moc \
 	$(gb_CustomTarget_workdir)/vcl/qt6/QtExpander.moc \

vcl/inc/qt5/QtAccessibleWidget.hxx

@@ -36,20 +36,27 @@ class XAccessibleTable;
 class QtFrame;
 class QtWidget;
 
-class QtAccessibleWidget final : public QAccessibleInterface,
+class QtAccessibleWidget final : public QObject,
+                                 public QAccessibleInterface,
                                  public QAccessibleActionInterface,
+#ifndef Q_MOC_RUN
 #if QT_VERSION >= QT_VERSION_CHECK(6, 8, 0)
                                  public QAccessibleAttributesInterface,
+#endif
 #endif
                                  public QAccessibleTextInterface,
                                  public QAccessibleEditableTextInterface,
+#ifndef Q_MOC_RUN
 #if QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
                                  public QAccessibleSelectionInterface,
+#endif
 #endif
                                  public QAccessibleTableCellInterface,
                                  public QAccessibleTableInterface,
                                  public QAccessibleValueInterface
 {
+    Q_OBJECT
+
 public:
     QtAccessibleWidget(const css::uno::Reference<css::accessibility::XAccessible>& xAccessible,
                        QObject* pObject);
@@ -88,6 +95,7 @@ public:
     void doAction(const QString& actionName) override;
     QStringList keyBindingsForAction(const QString& actionName) const override;
 
+#ifndef Q_MOC_RUN
 #if QT_VERSION >= QT_VERSION_CHECK(6, 8, 0)
     // helper method for QAccessibleAttributesInterface
     QHash<QAccessible::Attribute, QVariant> attributes() const;
@@ -95,6 +103,7 @@ public:
     // QAccessibleAttributesInterface
     QList<QAccessible::Attribute> attributeKeys() const override;
     QVariant attributeValue(QAccessible::Attribute key) const override;
+#endif
 #endif
 
     // QAccessibleTextInterface

vcl/qt5/QtAccessibleWidget.cxx

@@ -18,6 +18,7 @@
  */
 
 #include <QtAccessibleWidget.hxx>
+#include <QtAccessibleWidget.moc>
 
 #include <QtGui/QAccessibleInterface>