removeEventListener method
Implementation
@mustCallSuper
void removeEventListener(String eventType, EventHandler eventHandler) {
if (_disposed) return;
List<EventHandler>? currentHandlers = _eventHandlers[eventType];
if (currentHandlers != null) {
currentHandlers.remove(eventHandler);
if (currentHandlers.isEmpty) {
_eventHandlers.remove(eventType);
}
}
}