It is at the discretion of the tester. However, I think the article is fairly self explanatory.
They use sentences such as -
Vehicles with HID headlamps are therefore required to have a headlamp washing system (a wiper is not required) and be self levelling, which may be achieved either by the use of either headlamp or suspension levelling systems. HID is a term used to describe a group of headlights, Xenons (whether OEM or retrofit - still xenons) are in that group.
Not sure where the get out clause is in the above. But very happy to be proven wrong.
My whole reason for posting this was not to get anyone's back up, but to give information, there are a lot of enquiries on this site about Retrofitting Xenons, and HID Kits.