CL: https://chromium-review.googlesource.com/c/512623/

I tried to add eugenebut@chromium.org as a reviewer using the polygerrit UI by clicking on the "add reviewer" link. After filling the reviewer field and sending the message, the reviewer list is still empty, eugenebut@chromium.org is still only in the cc: field and was not in the to: field of the email sent when I added them to reviewer (which correspond to https://chromium-review.googlesource.com/c/512623/#message-e7f002eece21d29b6d38fbe9c185dabc3abd1e7b).

I also tried to add them as assignee, but they are still not in the to: line of the emails. This can be problematic if they have email filters that archives emails if they are not in the to: field.

Removing them from cc: allowed me to add them to the to:. I think that the UI should automatically remove people from cc: if they are manually added to to: (or allow people to be both in to: and cc:).