)
Adds error to the controller's stream.
As StreamController.addError, but must not be called while an event is being added by add, addError or close.
Source
/**
* Adds error to the controller's stream.
*
* As [StreamController.addError], but must not be called while an event is
* being added by [add], [addError] or [close].
*/
void addError(Object error, [StackTrace stackTrace]);