Javafx: Tableview header is not row bound

Question

Javafx: Tableview header is not row bound

Update Attached example code that shows the problem. I noticed that this happens when:

Displaying the table inside the grid panel with another control (e.g. Combobox), so the tableview headers are aligned with the grid
The first row of the table looks empty.

I am trying to use a TableView to display the name and TextField pair using the following code (Java8u66)

FXML

<TableView fx:id="AttributeValueTableView" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" GridPane.columnSpan="2" GridPane.rowIndex="1">
 <columns>
  <TableColumn fx:id="AttributeTableColumn" editable="false" minWidth="50.0" prefWidth="200.0" text="Attribute"/>
  <TableColumn fx:id="ValueTableColumn" maxWidth="1.7976931348623157E308" minWidth="50.0" prefWidth="400.0" text="Value"/>
 </columns>
 <columnResizePolicy>
  <TableView fx:constant="CONSTRAINED_RESIZE_POLICY"/>
 </columnResizePolicy>
</TableView>

controller

public class Controller implements Initializable {

@FXML
private TableView<AttributeValuePair> AttributeValueTableView;

@FXML
private TableColumn<AttributeValuePair, String> AttributeTableColumn;

@FXML
private TableColumn<AttributeValuePair, Object> ValueTableColumn;

private ObservableList<AttributeValuePair> valuePairs = FXCollections.observableArrayList();

@Override
public void initialize(URL location, ResourceBundle resources) {
    AttributeTableColumn.setCellValueFactory(new PropertyValueFactory<>("name"));
    ValueTableColumn.setCellFactory(param -> new AttributeValueCell());
    valuePairs.add(new AttributeValuePair("Attribute1"));
    valuePairs.add(new AttributeValuePair("Attribute2"));
    valuePairs.add(new AttributeValuePair("Attribute3"));
    valuePairs.add(new AttributeValuePair("Attribute4"));
    valuePairs.add(new AttributeValuePair("Attribute5"));
    valuePairs.add(new AttributeValuePair("Attribute6"));
    AttributeValueTableView.setItems(valuePairs);
}

private class AttributeValueCell extends javafx.scene.control.TableCell<AttributeValuePair, Object> {
    @Override
    protected void updateItem(Object item, boolean empty) {
        super.updateItem(item, empty);
        AttributeValuePair valuePair = (AttributeValuePair) this.getTableRow().getItem();
        if (empty || valuePair == null) {
            setGraphic(null);
            setText(null);
        } else {
            TextField t = new TextField();
            setGraphic(t);
        }
    }
}
}