Moved CEnableForDockWidgetInfoArea to ns BlackGui, was in BlackGui::Components for some reason

Discovered during T536

src/blackgui/enablefordockwidgetinfoarea.h

@@ -0,0 +1,71 @@
+/* Copyright (C) 2013
+ * swift project Community / Contributors
+ *
+ * This file is part of swift Project. It is subject to the license terms in the LICENSE file found in the top-level
+ * directory of this distribution and at http://www.swift-project.org/license.html. No part of swift project,
+ * including this file, may be copied, modified, propagated, or distributed except according to the terms
+ * contained in the LICENSE file.
+ */
+
+//! \file
+
+#ifndef BLACKGUI_ENABLEFORDOCKWIDGETINFOAREA_H
+#define BLACKGUI_ENABLEFORDOCKWIDGETINFOAREA_H
+
+#include "blackgui/blackguiexport.h"
+#include "blackmisc/connectionguard.h"
+
+namespace BlackGui
+{
+    class CDockWidgetInfoArea;
+    class CEnableForFramelessWindow;
+    class CInfoArea;
+
+    //! Helper class: If a component is residing in an dockable widget.
+    //! This class provides access to its info area and dockable widget.
+    class BLACKGUI_EXPORT CEnableForDockWidgetInfoArea
+    {
+    public:
+        //! Corresponding dockable widget in info area
+        CDockWidgetInfoArea *getDockWidgetInfoArea() const { return m_parentDockableInfoArea; }
+
+        //! Has dock area?
+        bool hasDockWidgetArea() const { return m_parentDockableInfoArea; }
+
+        //! Corresponding dockable widget in info area
+        //! \remarks Usually set from CDockWidgetInfoArea when it is fully initialized
+        virtual bool setParentDockWidgetInfoArea(CDockWidgetInfoArea *parentDockableWidget);
+
+        //! The parent info area
+        CInfoArea *getParentInfoArea() const;
+
+        //! Is the parent dockable widget floating?
+        bool isParentDockWidgetFloating() const;
+
+        //! \copydoc CDockWidgetInfoArea::isVisibleWidget
+        bool isVisibleWidget() const;
+
+        //! Main application window if any
+        CEnableForFramelessWindow *mainApplicationWindow() const;
+
+        //! Main application window widget if any
+        QWidget *mainApplicationWindowWidget() const;
+
+        //! Display myself
+        void displayMyself();
+
+    protected:
+        //! Constructor
+        //! \remarks Normally the info area will be provided later \sa setParentDockWidgetInfoArea
+        CEnableForDockWidgetInfoArea(CDockWidgetInfoArea *parentInfoArea = nullptr);
+
+        //! Destructor
+        virtual ~CEnableForDockWidgetInfoArea() {}
+
+    private:
+        CDockWidgetInfoArea *m_parentDockableInfoArea = nullptr; //!< my parent dockable widget
+        BlackMisc::CConnectionGuard m_connections;
+    };
+} // namespace
+
+#endif // guard