Overrides Entity::isNew().
EntityInterface::enforceIsNew() is only supported for newly created configuration entities but has no effect after saving, since each configuration entity is unique.
Overrides Entity::isNew
public final function isNew() {
// Configuration entity IDs are strings, and '0' is a valid ID.
return !empty($this->enforceIsNew) || $this
->id() === NULL || $this
->id() === '';
}