Re #6798 Allowed updateTree() to be called without free GUI thread

MantidPlot/src/Mantid/MantidDock.cpp

@@ -403,6 +403,7 @@ void MantidDockWidget::setItemIcon(QTreeWidgetItem *item,
 * It is important that the workspace tree is modified only by this method.
 */
 void MantidDockWidget::updateTree() {
+  // [Removed]
   // do not update until the counter is zero
   if (m_updateCount.deref())
     return;