{Fancy,Debugger}MainWindow: Consolidate dock actions menu population

There are several places where the list of dock actions are shown,
and at least two where it was created.

Change-Id: Ib2c18e602b5d6f57c1b7471bd75f3b989d536600
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

src/libs/utils/fancymainwindow.h

@@ -67,7 +67,7 @@ public:
     QAction *resetLayoutAction() const;
 
     // Overwritten to add locked/reset.
-    virtual QMenu *createPopupMenu();
+    void addDockActionsToMenu(QMenu *menu);
 
     QDockWidget *toolBarDockWidget() const;
     void setToolBarDockWidget(QDockWidget *dock);