Don't try to load user profile images in PhabricatorPeopleQuery if no users have any
Fixes T3810. In PhabricatorPeopleQuery, we issue an unnecessary query like this:
SELECT f.* FROM file f WHERE (f.phid IN ('')) ORDER BY f.id DESC
...if we're loading a user without a profile picture. Filter the file PHIDs before loading them to prevent this.
This doesn't change anything, but saves us a spurious/silly query.
Also makes PhabricatorPeopleProfileController use needProfileImage(), moving us closer to getting rid of loadProfileImageURI() eventually.
Test Plan: Looked at profiles of users with and without profile pictures. Checked query log in DarkConsole.
Reviewers: chad, btrahan
Reviewed By: chad
Maniphest Tasks: T3810
Differential Revision: https://secure.phabricator.com/D6913