Fix behavior of ldap_person method in Gitlab::OAuth::User
Code tweaks in 45e9150a caused the ldap_person method to not return expected results.
Improved tests to cover the ldap_person method, which was previously stubbed.
Restored the previous implementation of ldap_person, as I could not find a more concise to write it that still works with all the test cases.
See merge request !837
Until now, a user needed to first sign in with his LDAP identity and then manually
link his/her account with an omniauth identity from their profile.
Only when this is done can the user authenticate with the omniauth provider and at
the same time benefit from the LDAP integration (HTTPS authentication with LDAP
username/password and in EE: LDAP groups, SSH keys etc.).
This feature automates the process by looking up a corresponding LDAP person when a
user connects with omniauth for the first time and then automatically linking the LDAP
and omniauth identities (of course, like the existing allow_single_sign_on setting,
this is meant to be used with trusted omniauth providers).
The result is identical to a manual account link.
Add config initializers for other omniauth settings.
Douwe Maan
Alex Lossent
Onur Küçük
Robert Speicher