Get connection state after connect

A similar question was asked before but without a resolution. I want to get the connection state after I called HtmlWebSocketChannel.connect.
The reason is hat I want to display a successful connection in the statusbar and add the Url to a history list. Right now I can only get a callback if the connection failed. But that would only happen asynchronously after I connect.

channel = HtmlWebSocketChannel.connect('ws://' + url);
channel.stream.listen(
_receiveMessage,
onError: (e) {
print('Could not connect to: $url');
},
onDone: () {
print('Connection closed');
},
);
update_statusbar(url); // FIXME: here I do not know if the connection was successful or not!

Start at HtmlWebSocketChannel.connect and inspect how channel.stream reports errors and completion. Compare the existing asynchronous callbacks with the requested successful-connect signal; done means callers can reliably distinguish a successful connection from a failed one before updating the status bar or history.

Written by the indexing model from the issue text.