RFR: 8318204: Use new EventTarget methods in ListenerHelper

[Andy Goryachev]

On Tue, 17 Oct 2023 04:46:12 GMT, Michael Strauß <mstrauss at openjdk.org> wrote:

> As of OpenJFX 21, `EventTarget` has methods to add and remove event listeners.
> The `instanceof` checks in `com.sun.javafx.scene.control.ListenerHelper` should be removed and replaced by a simple call to the respective interface method.

🕶 looks good, thanks!

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Marked as reviewed by angorya (Reviewer).

PR Review: https://git.openjdk.org/jfx/pull/1262#pullrequestreview-1682519588