TrackballControls: Fixed bad zoom performance

[boulabiar]

The issue described in #14182 and #14013 is still present.

[Mugen87]

Since #14013 is still open, do you mind to close the issue? I don't think there is a benefit to have two issues for the same problem.

[boulabiar]

ok, I'll close it.
But I'm really confused what does #14622 actually fix to get merged and closed?
it pretends to fix #14182 and #14013 but the issue is still present.

[Mugen87]

The PR fixed an issue in context of overscroll-behavior("spongy" edges") and the related performance problem. @XanderLuciano explains the fix in the following video very well:

https://www.youtube.com/watch?v=QqQ-qKrXLoI

[boulabiar]

Ok, I hope one day I will be able to explain (and be understood) like him!
BTW, in that same video, and exactly at 1:47 to 1:50 it is still possible to view the problem happening after the "fix".