ADS: Remove struct from DockOverlay

We do not use struct on Qt Creator.

Change-Id: I61597081ecdcbc8fcfdc3c0317f83976b268cb7d
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/libs/advanceddockingsystem/dockoverlay.cpp

@@ -59,8 +59,9 @@ namespace ADS {
     /**
      * Private data class of DockOverlay
      */
-    struct DockOverlayPrivate
+    class DockOverlayPrivate
     {
+    public:
         DockOverlay *q;
         DockWidgetAreas m_allowedAreas = InvalidDockWidgetArea;
         DockOverlayCross *m_cross;
@@ -81,8 +82,9 @@ namespace ADS {
     /**
      * Private data of DockOverlayCross class
      */
-    struct DockOverlayCrossPrivate
+    class DockOverlayCrossPrivate
     {
+    public:
         DockOverlayCross *q;
         DockOverlay::eMode m_mode = DockOverlay::ModeDockAreaOverlay;
         DockOverlay *m_dockOverlay;
@@ -335,7 +337,7 @@ namespace ADS {
             pixmap.setDevicePixelRatio(devicePixelRatio);
             return pixmap;
         }
-    };
+    }; // class DockOverlayCrossPrivate
 
     DockOverlay::DockOverlay(QWidget *parent, eMode mode)
         : QFrame(parent)

src/libs/advanceddockingsystem/dockoverlay.h

@@ -48,7 +48,7 @@ QT_END_NAMESPACE
 
 namespace ADS {
 
-struct DockOverlayPrivate;
+class DockOverlayPrivate;
 class DockOverlayCross;
 
 /**
@@ -60,7 +60,7 @@ class ADS_EXPORT DockOverlay : public QFrame
     Q_OBJECT
 private:
     DockOverlayPrivate *d; //< private data class
-    friend struct DockOverlayPrivate;
+    friend class DockOverlayPrivate;
     friend class DockOverlayCross;
 
 public:
@@ -130,7 +130,7 @@ protected:
     virtual void hideEvent(QHideEvent *event) override;
 };
 
-struct DockOverlayCrossPrivate;
+class DockOverlayCrossPrivate;
 /**
  * DockOverlayCross shows a cross with 5 different drop area possibilities.
  * I could have handled everything inside DockOverlay, but because of some
@@ -176,7 +176,7 @@ public:
 
 private:
     DockOverlayCrossPrivate *d;
-    friend struct DockOverlayCrossPrivate;
+    friend class DockOverlayCrossPrivate;
     friend class DockOverlay;
 
 protected: