DataGrid.ItemClickEvent always returns null for columnId value

[glebfox]

Environment

• Platform version: 7.0.3

Description of the bug or enhancement

• Minimal reproducible example

<window xmlns="http://schemas.haulmont.com/cuba/screen/window.xsd">
    <data>
        <collection id="customersDc"
                    class="com.haulmont.sampler.entity.Customer"
                    view="_local">
            <loader id="customersLoader">
                <query>
                    <![CDATA[select e from sampler$Customer e]]>
                </query>
            </loader>
        </collection>
    </data>
    <layout expand="customersDataGrid">
        <dataGrid id="customersDataGrid"
                  dataContainer="customersDc"
                  width="100%">
            <actions>
                <action id="create" type="create"/>
                <action id="edit" type="edit"/>
                <action id="remove" type="remove"/>
                <action id="excel" type="excel"/>
                <action id="greeting"
                        caption="Greeting"/>
            </actions>
            <columns>
                <column id="nameId" property="name"/>
                <column property="lastName"/>
                <column property="age"/>
                <column property="active"/>
                <column property="grade"/>
            </columns>
            <buttonsPanel>
                <button action="customersDataGrid.create"/>
                <button action="customersDataGrid.edit"/>
                <button action="customersDataGrid.remove"/>
                <button action="customersDataGrid.excel"/>
                <button action="customersDataGrid.greeting"/>
            </buttonsPanel>
        </dataGrid>
    </layout>
</window>

@UiController("datagrid-actions")
@UiDescriptor("datagrid-actions.xml")
@LoadDataBeforeShow
public class DataGridActionsSample extends ScreenFragment {
    @Inject
    private Notifications notifications;

    @Subscribe("customersDataGrid")
    private void onCustomersDataGridItemClick(DataGrid.ItemClickEvent<Customer> event) {
        notifications.create()
                .withCaption(event.getColumnId())
                .show();
    }
}

• Expected behavior

event.getColumnId() returns either column Id or property Id

• Actual behavior

event.getColumnId() returns null

[pribavkindenis]

For QA:
See com.haulmont.cuba.web.gui.components.WebAbstractDataGrid#onItemClick