The parent node's state remains "unchecked".
The parent node's state should be "indeterminate".
Workaround:
Attach a DataBound event handler to the TreeView:
<kendo-treeview name="DataRestrictionTree" load-on-demand="false" datatextfield="Name" on-data-bound="onDataBound" >
In the handler call the TreeView's updateIndeterminate API method:
function onDataBound(e) {
var treeview = $("#DataRestrictionTree").data("kendoTreeView");
treeview.updateIndeterminate();
}