Assigns a particular ImageStreamCompleter to this ImageStream.
This is usually done automatically by the ImageProvider that created the ImageStream.
Source
void setCompleter(ImageStreamCompleter value) {
assert(_completer == null);
_completer = value;
if (_listeners != null) {
final List<ImageListener> initialListeners = _listeners;
_listeners = null;
initialListeners.forEach(_completer.addListener);
}
}