Move PHUIFormBoxView to PHUIObjectBoxView

Summary: I'd like to reuse this for other content areas, renaming for now. This might be weird to keep setForm, but I can fix that later if we need.

Test Plan: reload a few forms in maniphest, projects, differential

Reviewers: epriestley, btrahan

Reviewed By: epriestley

CC: Korvin, aran

Differential Revision: https://secure.phabricator.com/D7120

src/applications/project/controller/PhabricatorProjectMembersEditController.php

@@ -106,11 +106,11 @@ final class PhabricatorProjectMembersEditController
         id(new AphrontFormInsetView())
           ->appendChild($list));
 
-    $box = id(new PHUIFormBoxView())
+    $box = id(new PHUIObjectBoxView())
       ->setHeaderText(pht('Current Members (%d)', count($handles)))
       ->setForm($faux_form);
 
-    $form_box = id(new PHUIFormBoxView())
+    $form_box = id(new PHUIObjectBoxView())
       ->setHeaderText($title)
       ->setForm($form);