Outgoing constructor

*[<Null safety>](https://dart.dev/null-safety)*

Outgoing()

This will setup outgoing directory and add required directories to root of this class.

This class will throw an Exception if its methods are called after it is closed. Calling close twice doesn't cause exception.

Implementation

Outgoing() {
  // TODO(fxbug.dev/4427): remove 'public' after transition is complete
  _root
    ..addNode('public', _public)
    ..addNode('svc', _public)
    ..addNode('debug', _debug)
    ..addNode('diagnostics', _diagnostics)
    ..addNode('ctrl', _ctrl);
}