KFileItemModel: Fix triggering of wrong assertion

When switching from the details-mode of a search-view into any other
mode, the m_expandedParentsCountRoot is set to ForceExpandedParentsCountRoot.

src/kitemviews/kfileitemmodel.cpp

@@ -1084,7 +1084,6 @@ void KFileItemModel::removeExpandedItems()
 
     // The m_expandedParentsCountRoot may not get reset before all items with
     // a bigger count have been removed.
-    Q_ASSERT(m_expandedParentsCountRoot >= 0);
     removeItems(expandedItems);
 
     m_expandedParentsCountRoot = UninitializedExpandedParentsCountRoot;