Core: Use Qt5-style connects

The heavy lifting was done by clazy.

Change-Id: I2dde14919d917816d02117338205f8f861d8af0a
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

src/plugins/coreplugin/fancytabwidget.h

@@ -167,10 +167,9 @@ public slots:
     void setCurrentIndex(int index);
     void setSelectionWidgetVisible(bool visible);
 
-private slots:
+private:
     void showWidget(int index);
 
-private:
     FancyTabBar *m_tabBar;
     QWidget *m_cornerWidgetContainer;
     QStackedLayout *m_modesStack;