Remove arcanist projects from differential

Summary: Ref T7604. Remove arcanist projects from differential. Depends on D12687 and D12893.

Test Plan: Submitted a diff. Patched the diff with `arc patch`.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: Korvin, epriestley

Maniphest Tasks: T7604

Differential Revision: https://secure.phabricator.com/D12894

src/applications/differential/controller/DifferentialRevisionViewController.php

@@ -33,7 +33,6 @@ final class DifferentialRevisionViewController extends DifferentialController {
     $diffs = id(new DifferentialDiffQuery())
       ->setViewer($request->getUser())
       ->withRevisionIDs(array($this->revisionID))
-      ->needArcanistProjects(true)
       ->execute();
     $diffs = array_reverse($diffs, $preserve_keys = true);