Code review comment for lp:~gary-wzl77/account-plugins/onedrive_provider

Yes, I hit the same problem if user's not accepted the terms & conditions yet.

1...Return an empty username instead of calling cancel
Basically, I think empty username is sth we need to avoid since we have been discussing this issue with michi and james that users can't distinguish two Microsoft account when they have two microsoft account logged in if they hit the above problem. Yes, I know it's a rare case.
2. Maybe we should use the user ID only if the user name is empty. Can you please change this?
The reason why I append user id here is that Microsoft didn't provider user email address in response body so that there is probably a rare case that two same accounts (e.g. two "Gary" in display name field) are shown in account page, which makes users confused.

However, I saw your merge proposal, You call cancel() if user name is not be obtained and still append user id into display name, which look good.