Repro case for https://bugs.openjdk.java.net/browse/JDK-8187912

cellfactorytest.scala

package cellfactory

import javafx.application.Application
import javafx.collections.FXCollections
import javafx.scene.control.ListView
import javafx.scene.layout.StackPane
import javafx.scene.{Scene, control => jfxsc}
import javafx.stage.Stage
import javafx.util.Callback

class TestLauncher extends Application {
    def start(stage: Stage): Unit = {
        val javafxComboBox = new jfxsc.ComboBox[MyCustomClass]()
        val cellFactoryCallback = new Callback[jfxsc.ListView[MyCustomClass], jfxsc.ListCell[MyCustomClass]] {
            override def call(param: ListView[MyCustomClass]) = new jfxsc.ListCell[MyCustomClass] {
                // Customize the appearance of the cell.
                override def updateItem(item: MyCustomClass, empty: Boolean): Unit = {
                    super.updateItem(item, empty)

                    if (empty || item == null) {
                        setText(null)
                        setGraphic(null)
                    } else {
                        setText("Good toString")
                    }
                }
            }
        }
        javafxComboBox.setCellFactory(cellFactoryCallback)
        javafxComboBox.getSelectionModel.selectFirst()
        javafxComboBox.setItems(FXCollections.observableArrayList(MyCustomClass("blah"), MyCustomClass("blahhh")))

        val root = new StackPane()
        root.getChildren.add(javafxComboBox)
        stage.setScene(new Scene(root))
        stage.show()
    }
}

object TestLauncher {
    def main(args: Array[String]): Unit = {
        Application.launch(classOf[TestLauncher])
    }
}

case class MyCustomClass(str: String) {
    override def toString = "Bad toString"
}