Revert 9.x events changes

[MylesBorins]

It appears that 3ae5cf2 may have been Semver-Major as it broke the following code sample

var assert = require('assert')
var EventsModule = require('events')
var descriptor = Object.getOwnPropertyDescriptor(EventsModule, 'usingDomains')
assert(descriptor)

This PR reverts 3ae5cf2 and the two commits that were backported along side of it 28edc1d and 35471bc

We should likely get a new release out of the door asasp

/cc @watson

[addaleax]

Isn’t it, like, pretty trivial to just add back EventEmitter.usingDomains = false; instead?

[addaleax]

To be clear, I’m basically suggesting only taking this line of the diff, and leaving the rest alone

[MylesBorins]

I'm open to that as well, wasn't sure the context or why that line was removed. Should we add that line back to master instead?

Would doing another release next tuesday make sense then or should we get this out asap

[addaleax]

@MylesBorins I guess it seems fair to remove the line because it would be false-y by default anyway, so explicitly setting it here and thereby leaking domains logic into this module seems undesirable.

Would doing another release next tuesday make sense then or should we get this out asap

It’s not really all that clear to me just how breaking this change is or how many people it would affect – but if we’re only adding this line back, I don’t see a reason not to do a release as soon as we can.

[MylesBorins]

Ok opening a PR

[fhinkel]

+1 to @addaleax 's suggestion.

[vdeturckheim]

+1 on @addaleax