Called by the link internals to set an attribute on this node.
Source
Response setAttribute(
String name, Object value, Responder responder, Response response) {
if (response != null) {
return response..close();
} else {
if (!name.startsWith("@")) {
name = "@${name}";
}
attributes[name] = value;
if (provider is SerializableNodeProvider) {
(provider as SerializableNodeProvider).persist();
}
return null;
}
}