GUAC-1391: Skip readable check when listing active sessions for system administrators.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-base/src/main/java/org/glyptodon/guacamole/auth/jdbc/tunnel/AbstractGuacamoleTunnelService.java

@@ -468,6 +468,10 @@ public abstract class AbstractGuacamoleTunnelService implements GuacamoleTunnelS
         if (records.isEmpty())
             return Collections.<ActiveConnectionRecord>emptyList();
 
+        // A system administrator can view all connections; no need to filter
+        if (user.getUser().isAdministrator())
+            return records;
+
         // Build set of all connection identifiers associated with active tunnels
         Set<String> identifiers = new HashSet<String>(records.size());
         for (ActiveConnectionRecord record : records)