$data['node_field_revision']['nid']['relationship']['base field'] = 'nid';
$data['node_field_revision']['nid']['relationship']['title'] = $this->t('Content');
$data['node_field_revision']['nid']['relationship']['label'] = $this->t('Get the actual content from a content revision.');
$data['node_field_revision']['nid']['relationship']['base field'] = 'nid';
$data['node_field_revision']['nid']['relationship']['title'] = $this->t('Content');
$data['node_field_revision']['nid']['relationship']['label'] = $this->t('Get the actual content from a content revision.');