iOS: Add support for the throttling in Network tab

[SuperPat45]

I notice the throttling option in the Network tab does not have any effects.

Would it be possible to make it work?

[auchenberg]

Thanks for filing this. I doubt it, as Webkit don't have such APIs per my understanding, but let's try to figure it out.

[auchenberg]

Looks like this is the way is to do it in iOS, https://nshipster.com/network-link-conditioner.

I wonder if there's any APIs available.