[iOS] Fabric: Fixes Modal snapshot when closing it

[zhongwuzw]

Summary:

Fixes #48245 . The reason is we reuse the modal component and also reuse the snapshot of previous modal.

Changelog:

[IOS] [FIXED] - Fabric: Fixes Modal snapshot when closing it

Test Plan:

Repro repo please see Fixes #48245

[zhongwuzw]

@cortinico Hi, can you help to review this? ：）

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[cipolleschi]

Thanks @zhongwuzw for working on this. Unfortunately we might not be able to land this fix: this was how the code was before we moved the creation of the snapshot, but it was creating performance issues with the present/dismiss animations in our apps, that's why we had to move the code around.

We are aware that the current situation is not optimal, but we are investigating alternative ways to handle this.

[zhongwuzw]

@cipolleschi Hi, thanks for the review, I saw the history of this , did you mean this commit zhongwuzw@30d6251 ? I think maybe my changes not much difference with current implementation, and also only snapshot once when dismiss modal.

[cipolleschi]

Yes, that was the original change.
I can try your fix and see how it behave, but if it degrades the animation performance we would have to revert it. :(