Constructs the overview object for a entity type, bundle and view mode.
string $entity_type: The entity type.
string $bundle: The bundle for the entity of entity_type.
string $view_mode: (optional) The view mode for the entity which takes a string or "default".
public function __construct($entity_type, $bundle, $view_mode = NULL) {
$this->entity_type = $entity_type;
$this->bundle = $bundle;
$this->view_mode = isset($view_mode) ? $view_mode : 'default';
$this->adminPath = field_ui_bundle_admin_path($this->entity_type, $this->bundle);
}