RFR: 8369306: Implement invokeAndWait and finishTerminating on headless platform [v3]

[Johan Vos]

On Mon, 13 Oct 2025 16:36:21 GMT, Kevin Rushforth <kcr at openjdk.org> wrote:

>> I agree with @johanvos , it's always better to wait for the lock (with a timeout)
>
> Better, sure, but it isn't always possible in practice. There are times where a delay is still needed.
> 
> This test now waits for the lock on the condition that will lead to the thread shutting down. Good. It's still necessary to sleep for a small time to be sure that it has.

As I said in my previous comment, I don't see this as a showstopper for this PR, but since it might help in general, I keep thinking about approaches to remove the sleep.
Wouldn't it be an option here to obtain the JavaFX Application Thread after the `assertTrue(Platform.isFxApplicationThread());` and assign it to e.g. `Thread fxThread` so that instead of the `Util.sleep` we can do `fxThread.join(10)` ? (I might be missing something though)

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PR Review Comment: https://git.openjdk.org/jfx/pull/1934#discussion_r2426918545