Ever since protocol.js was added as a way to create DevTools actors, we've had
lots of confusion about the correct way to implement actor destruction. If your
actor's _parent_ was the legacy kind, you had to use `disconnect`. If it was
protocol.js, you had to use `destroy`.
There is no reason for this madness, which makes reasoning about destruction
quite hard. Here we rename `disconnect` to `destroy` so there is only one name
for every destruction path.
MozReview-Commit-ID: C1Yw9NfUUR2
Expose network throttling via the emulation actor, similar to other platform
features that RDM alters. This simplifies the client side since we can avoid
thinking about console clients, etc.
MozReview-Commit-ID: 3CNnJl6Ude8
