This isn't Chrome going against the spec. This is the spec's author (who happens to work on Chrome) changing the spec. Since the spec is still in draft, change

This isn't Chrome going against the spec. This is the spec's author (who happens to work on Chrome) changing the spec. Since the spec is still in draft, changes are expected. This isn't even the first change, we're already on version 3. And this version expires next month, so we're literally, explicitly, due for a new revision.