Unit test CallbackTest.testCloseWindow fails with WebKit 614.1

On executing CallbackTest > testCloseWindow test with webkit614.1 , its is observed that the test fails with below error:

CallbackTest > testCloseWindow FAILED
    java.lang.AssertionError: Method onVisibilityChanged was not called with args: false,
        at org.junit.Assert.fail(Assert.java:89)
        at test.javafx.scene.web.CallbackTest$TestUI.checkCalled(CallbackTest.java:263)
        at test.javafx.scene.web.CallbackTest.testCloseWindow(CallbackTest.java:164)