Protected allthe rows to uncheck together with their descendants; default: the root nodes (whole tree)
const checkboxModel = new TreeCheckboxModel(TreeFactory.buildTreeRows<OrderNode>(nodes));
checkboxModel.checkAll(); // uncheck every row of the tree
Unchecks the given rows and all their descendants – despite its name, like CheckboxModel.checkAll (which clears all checked rows). The parents of the given rows are updated ("semi" or "none").