Summary:
- We currently have some bugs in account creation due to nontransactional user/email editing.
- We save $user, then try to save $email. This may fail for various reasons, commonly because the email isn't unique.
- This leaves us with a $user with no email.
- Also, logging of edits is somewhat inconsistent across various edit mechanisms.
- Move all editing to a `PhabricatorUserEditor` class.
- Handle some broken-data cases more gracefully.
Test Plan:
- Created and edited a user with `accountadmin`.
- Created a user with `add_user.php`
- Created and edited a user with People editor.
- Created a user with OAuth.
- Edited user information via Settings.
- Tried to create an OAuth user with a duplicate email address, got a proper error.
- Tried to create a user via People with a duplicate email address, got a proper error.
Reviewers: btrahan, vrana, jungejason
Reviewed By: btrahan
CC: tberman, aran
Maniphest Tasks: T1184
Differential Revision: https://secure.phabricator.com/D2569
