RFR: 8269907 memory leak - Dirty Nodes / Parent removed [v5]

[Florian Kirmaier]

On Thu, 27 Jan 2022 14:50:16 GMT, Florian Kirmaier <fkirmaier at openjdk.org> wrote:

>> After thinking about this issue for some time, I've now got a solution.
>> I know put the scene in the state it is, before is was shown, when the dirtyNodes are unset, the whole scene is basically considered dirty. 
>> This has the drawback of rerendering, whenever a window is "reshown", but it restores sanity about memory behaviour, which should be considered more important.
>
> Florian Kirmaier has updated the pull request incrementally with one additional commit since the last revision:
> 
>   JDK-8269907
>   Removed the sync methods for the scene, because they don't work when peer is null, and they are not necessary.

I've just merged it with master, to make it easier to review, if someone finds the time.

-------------

PR: https://git.openjdk.org/jfx/pull/584