minor refactoring: return a more generic type

SVN: 9623

openbis/source/java/ch/systemsx/cisd/openbis/generic/client/web/client/application/framework/DefaultTabItem.java

@@ -44,7 +44,7 @@ public class DefaultTabItem implements ITabItem
         this(title, component, isCloseConfirmationNeeded, null);
     }
 
-    public static DefaultTabItem create(final String title, final DisposableComponent component,
+    public static ITabItem create(final String title, final DisposableComponent component,
             boolean isCloseConfirmationNeeded)
     {
         Listener<TabPanelEvent> eventListener = createCloseEventListener(component);