I wonder why there is a difference between $id and $this->getState('article.id') in edits. I'd have to dig through where this state is set.
However I'd say if that PR broke it by changing from $this->getState('article.id') to $id and reverting that line fixes it. Then go with that approach. It was only a sidechange in that PR anyway.
Is this a side effect of #3944 ?