ADS: Remove struct from FloatingDragPreview

Change-Id: Ib254b9eff1a2a5bd6951d5c9c59c9290664c2c89
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/libs/advanceddockingsystem/dockcontainerwidget.h

@@ -54,8 +54,8 @@ struct DockManagerPrivate;
 class FloatingDockContainer;
 class FloatingDockContainerPrivate;
 class FloatingDragPreview;
-struct FloatingDragPreviewPrivate;
 class DockingStateReader;
+class FloatingDragPreviewPrivate;
 
 /**
  * Container that manages a number of dock areas with single dock widgets
@@ -78,7 +78,7 @@ private:
     friend class FloatingDockContainerPrivate;
     friend class DockWidget;
     friend class FloatingDragPreview;
-    friend struct FloatingDragPreviewPrivate;
+    friend class FloatingDragPreviewPrivate;
 
 protected:
     /**

src/libs/advanceddockingsystem/dockmanager.h

@@ -106,7 +106,7 @@ private:
     friend struct DockAreaWidgetPrivate;
     friend struct DockWidgetTabPrivate;
     friend class FloatingDragPreview;
-    friend struct FloatingDragPreviewPrivate;
+    friend class FloatingDragPreviewPrivate;
     friend class DockAreaTitleBar;
 
 protected:

src/libs/advanceddockingsystem/floatingdragpreview.cpp

@@ -56,8 +56,9 @@ namespace ADS
     /**
      * Private data class (pimpl)
      */
-    struct FloatingDragPreviewPrivate
+    class FloatingDragPreviewPrivate
     {
+    public:
         FloatingDragPreview *q;
         QWidget *m_content;
         DockAreaWidget *m_contentSourceArea = nullptr;
@@ -91,8 +92,7 @@ namespace ADS
             m_dockManager->dockAreaOverlay()->hideOverlay();
             q->close();
         }
-    };
-    // struct FloatingDragPreviewPrivate
+    }; // class FloatingDragPreviewPrivate
 
     void FloatingDragPreviewPrivate::updateDropOverlays(const QPoint &globalPosition)
     {

src/libs/advanceddockingsystem/floatingdragpreview.h

@@ -43,7 +43,7 @@ namespace ADS {
 
 class DockWidget;
 class DockAreaWidget;
-struct FloatingDragPreviewPrivate;
+class FloatingDragPreviewPrivate;
 
 /**
  * A floating overlay is a temporary floating widget that is just used to
@@ -56,7 +56,7 @@ class FloatingDragPreview : public QWidget, public AbstractFloatingWidget
     Q_OBJECT
 private:
     FloatingDragPreviewPrivate *d;
-    friend struct FloatingDragPreviewPrivate;
+    friend class FloatingDragPreviewPrivate;
 
     /**
      * Cancel non opaque undocking if application becomes inactive