refs #757, materialize filtered data

* menu item / flag
* functions in view class
* some minor formatting

src/blackgui/models/listmodelbase.h

@@ -37,7 +37,6 @@ class QMimeData;
 class QModelIndex;
 
 namespace BlackMisc { class CWorker; }
-
 namespace BlackGui
 {
     namespace Models
@@ -205,6 +204,9 @@ namespace BlackGui
             //! Used container data
             const ContainerType &container() const;
 
+            //! Used container data
+            const ContainerType &containerFiltered() const;
+
             //! Full container or cached filtered container as approproiate
             const ContainerType &containerOrFilteredContainer() const;