UuidLookup: allow multi-key objects

Hint: we do not (yet) support templates in branches, but we need to deal
with related lookups

library/Director/Db/Branch/UuidLookup.php

@@ -90,7 +90,7 @@ class UuidLookup
         $query = self::addKeyToQuery($connection, $db->select()->from($table, 'uuid'), $key);
         $uuid = self::fetchOptionalUuid($connection, $query);
         if ($uuid === null && $branch->isBranch()) {
-            $query = $db->select()->from("branched_$table", 'uuid')->where('object_name = ?', $key);
+            $query = self::addKeyToQuery($connection, $db->select()->from("branched_$table", 'uuid'), $key);
             $uuid = self::fetchOptionalUuid($connection, $query);
         }