Add support in {add,remove}EventListener for stopPropagation and preventDefault options when passive: true

[dead-claudia]

This could still enable support for those features while retaining the perf improvements from using passive: true.

[annevk]

stopPropagation() isn't blocked to begin with and I don't see how you could enable preventDefault() without losing the benefits. The whole point is that you can't cancel the event.

[dead-claudia]

I mean, effectively this:

var old = EventTarget.prototype.addEventListener
EventTarget.prototype.addEventListener = function (listener, opts) {
    if (opts == null || !opts.passive || !opts.stopPropagation && !opts.preventDefault) {
        old.call(this, listener, opts)
    } else {
        const {stopPropagation, preventDefault} = opts
        old.call(this, ev => {
            if (stopPropagation) ev.stopPropagation()
            if (preventDefault) ev.preventDefault()
            return listener(ev)
        }, opts)
    }
}

Although, now that I think about it, the things affecting rendering performance (like scrolling) already have other ways of disabling them (like via CSS), so this would literally provide no benefit.