Fix infinite loop in renderAccessDenied()

Summary:
Fixes T8727. When I added `setParentQuery()`, I increased the cache hit rate but also accidentally propagated policy exception settings.

Instead, make the policy exception beahvior explicit: no exceptions should be raised when querying handles.

Test Plan: Will test production.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T8727

Differential Revision: https://secure.phabricator.com/D13489

src/applications/phid/query/PhabricatorHandleQuery.php

@@ -37,6 +37,12 @@ final class PhabricatorHandleQuery
       ->requireCapabilities($this->getRequiredObjectCapabilities())
       ->setViewer($this->getViewer());
 
+    // We never want the subquery to raise policy exceptions, even if this
+    // query is being executed via executeOne(). Policy exceptions are not
+    // meaningful or relevant for handles, which load in an "Unknown" or
+    // "Restricted" state after encountering a policy violation.
+    $object_query->setRaisePolicyExceptions(false);
+
     $objects = $object_query->execute();
     $filtered = $object_query->getPolicyFilteredPHIDs();