Add missing dispose() methods

[acu192]

Fixed #21572

[mrdoob]

Seems like the docs changes use spaces for indentation instead of tabs.

[acu192]

@mrdoob Fixed now.

[mrdoob]

Thanks!

[JaidenDeChon]

After updating recently, I found dispose() is also missing from Scene. Was this intentional? If it was intentional, is there a replacement or does the move to webgl2 mean we don't need this anymore?

Please let me know if I'm asking in the wrong place and I'll move this question. Thank you

[acu192]

After updating ...

Was there ever a dispose() in the Scene? If so, I never noticed it.

I don't think Scene needs one; the Scene itself does not create disposable objects. Rather, you create disposable objects and add them to the Scene. The purpose of dispose() is to dispose of resources that are created internally by the object.

For a larger discussion, you should probably file a new issue for it since this PR is already merged.

[Mugen87]

Was there ever a dispose() in the Scene?

Yes. And it was removed in #19972 after internal data-structures of the engine where converted to weak maps.