Update Gaia API documents for #abd571f4e567d4647c8b9c59f85ca293ffcd6ebf
    Merge pull request #14182 from gtorodelvalle/contacts-bug-936250-facebook-sync

Bug 936250 - [B2G][Contacts] Canceling FB sync results in the contacts app being unresponsive.
(cherry picked from commit 6e59c3cd7a793303695521e387c9ce09c2ecb7aa)