Use DifferentialRevisionQuery in differential controllers

Summary:
Change all instances of `id(new DifferentialRevision())->load($id)` for `DifferentialRevisionQuery` where reviewers are loaded.
Also make sure that the new reviewer status is being loaded so that all calls to `getReviewers` can be removed in the near future.

Test Plan: Use all three controllers with several revisions and check they still work in sane way

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T1279

Differential Revision: https://secure.phabricator.com/D6466

src/applications/differential/controller/DifferentialRevisionEditController.php

@@ -20,15 +20,17 @@ final class DifferentialRevisionEditController extends DifferentialController {
       $revision = id(new DifferentialRevisionQuery())
         ->setViewer($viewer)
         ->withIDs(array($this->id))
+        ->needRelationships(true)
+        ->needReviewerStatus(true)
         ->executeOne();
       if (!$revision) {
         return new Aphront404Response();
       }
     } else {
       $revision = new DifferentialRevision();
+      $revision->attachRelationships(array());
     }
 
-    $revision->loadRelationships();
     $aux_fields = $this->loadAuxiliaryFields($revision);
 
     $diff_id = $request->getInt('diffID');

src/applications/differential/controller/DifferentialRevisionViewController.php

@@ -18,13 +18,17 @@ final class DifferentialRevisionViewController extends DifferentialController {
     $user = $request->getUser();
     $viewer_is_anonymous = !$user->isLoggedIn();
 
-    $revision = id(new DifferentialRevision())->load($this->revisionID);
+    $revision = id(new DifferentialRevisionQuery())
+      ->withIDs(array($this->revisionID))
+      ->setViewer($request->getUser())
+      ->needRelationships(true)
+      ->needReviewerStatus(true)
+      ->executeOne();
+
     if (!$revision) {
       return new Aphront404Response();
     }
 
-    $revision->loadRelationships();
-
     $diffs = $revision->loadDiffs();
 
     if (!$diffs) {

src/applications/differential/controller/DifferentialSubscribeController.php

@@ -15,7 +15,12 @@ final class DifferentialSubscribeController extends DifferentialController {
     $request = $this->getRequest();
     $user = $request->getUser();
 
-    $revision = id(new DifferentialRevision())->load($this->id);
+    $revision = id(new DifferentialRevisionQuery())
+      ->withIDs(array($this->id))
+      ->setViewer($request->getUser())
+      ->needRelationships(true)
+      ->needReviewerStatus(true)
+      ->executeOne();
     if (!$revision) {
       return new Aphront404Response();
     }
@@ -51,7 +56,6 @@ final class DifferentialSubscribeController extends DifferentialController {
       return id(new AphrontDialogResponse())->setDialog($dialog);
     }
 
-    $revision->loadRelationships();
     $phid = $user->getPHID();
 
     switch ($this->action) {