[Perf improvement] move bind to Arrow functions

[RaananW]

This is a suggestion to move every bind(this) call to use arrow functions, as they are much faster.

I especially want to move the render function binding in the engine to use arrow function.

This is just a suggestion, and of course can be discussed.

[RaananW]

A basis for the discussion is this:

I can't seem to share this perf test for some reason ATM. working on that. This is the result of defining the function and running it as part of the perf test.

[bjsplat]

Please make sure to label your PR with "bug", "new feature" or "breaking change" label(s).
To prevent this PR from going to the changelog marked it with the "skip changelog" label.

[bjsplat]

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