SSDM-4187: Bug fixed: Tree expansion on filtered entries can show same child twice.

SVN: 38086

datastore_server/source/java/ch/systemsx/cisd/openbis/dss/client/api/gui/tree/FilterableMutableTreeNode.java

@@ -208,6 +208,17 @@ public class FilterableMutableTreeNode extends DefaultMutableTreeNode
         filter(getPattern());
     }
 
+    
+    @Override
+    public void remove(int childIndex)
+    {
+        Object removed = getFiltered().remove(childIndex);
+        if (removed != null)
+        {
+            children.remove(removed);
+        }
+    }
+
     @Override
     public void removeAllChildren()
     {