Show warning when no handler is registered.

src/app/spreed-speakfreely-server/sessions.go

@@ -91,13 +91,15 @@ func (sessions *Sessions) Patch(request *http.Request) (int, interface{}, http.H
 			error = true
 			log.Println("Session patch failed - users validation failed.", err)
 		}
-	}
-
 		// Make sure that we have a user.
 		if userid == "" {
 			error = true
 			log.Println("Session patch failed - userid empty.")
 		}
+	} else {
+		log.Println("Session patch failed - no handler.")
+		error = true
+	}
 
 	var nonce string
 	if !error {