Todo: added ability to filter todo list by keywords

Change-Id: I4be35caf461e50e256527ca72993f5d83d08ef3e
Reviewed-by: hjk <hjk@qt.io>

src/plugins/todo/todoitemsmodel.cpp

@@ -141,6 +141,7 @@ void TodoItemsModel::sort(int column, Qt::SortOrder order)
     m_currentSortOrder = order;
 
     TodoItemSortPredicate predicate(m_currentSortColumn, m_currentSortOrder);
+    emit layoutAboutToBeChanged();
     Utils::sort(*m_todoItemsList, predicate);
     emit layoutChanged();
 }