Sets the form entity.
Sets the form entity which will be used for populating form element defaults. Usually, the form entity gets updated by \Drupal\Core\Entity\EntityFormControllerInterface::submit(), however this may be used to completely exchange the form entity, e.g. when preparing the rebuild of a multi-step form.
\Drupal\Core\Entity\EntityInterface $entity: The entity the current form should operate upon.
array $form_state: An associative array containing the current state of the form.
public function setEntity(EntityInterface $entity, array &$form_state);