DropDownTree with remote binding does not truly selects inner checked items

[eyupyusein]

Bug report

The DropDownTree component provides built-in CheckBoxes. It also has the internal checked property which should initially check individual items. But in the scenario below, the inner items are not truly getting selected.

Reproduction of the problem

1. Create a new Core page.
2. Add the DropDownTree definition:

@using Kendo.Mvc.UI

@(Html.Kendo().DropDownTree()
        .Name("dropdowntree")
        .DataTextField("Name")
        .Checkboxes(true)
        .AutoClose(false)
        .DataSource(dataSource => dataSource
            .Read(read => read
                .Action("Remote_Data_Binding_Get_Employees", "Home")
            )
        )
    )

3. Create the model and add the data in the controller:

    public class Employee
    {
        public int EmployeeID { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public int? ReportsTo { get; set; }
        public bool Expanded { get; set; }
        public bool Checked { get; set; }
    }
    public JsonResult Remote_Data_Binding_Get_Employees(int? id)
    {
        var source = new List<Employee>();
        source.Add(new Employee() { EmployeeID = 1, FirstName = "Name", LastName = "1", Expanded = true });
        source.Add(new Employee() { EmployeeID = 2, FirstName = "Name", LastName = "2", Checked = true });
        source.Add(new Employee() { EmployeeID = 3, FirstName = "Name", LastName = "3", ReportsTo = 1, Checked = true });

        var employees = from e in source
                        where (id.HasValue ? e.ReportsTo == id : e.ReportsTo == null)
                        select new
                        {
                            id = e.EmployeeID,
                            expanded = e.Expanded,
                            @checked = e.Checked,
                            Name = e.FirstName + " " + e.LastName,
                            hasChildren = (from q in source
                                           where (q.ReportsTo == e.EmployeeID)
                                           select q
                                           ).Count() > 0
                        };

        return Json(employees);
    }

4. The inner item is visually selected, but in reality - it's not. The input does not show it and also the .value() method does not include it: