[cronet_http] StreamedResponse does not close after cancelling the response stream

[Colton127]

In cronet_http, cancelling the stream on a StreamedResponse does not close the underlying connection.

final engine = CronetEngine.build(cacheMode: CacheMode.disabled);
final client = CronetClient.fromCronetEngine(engine, closeEngine: true);
final request = Request('GET', Uri.parse('https://cachefly.cachefly.net/100mb.test'));
final streamedResponse = await client.send(request);
final streamSubscription = streamedResponse.stream.listen(null);
await Future.delayed(const Duration(seconds: 5));
await streamSubscription.cancel();

Despite the stream subscription being cancelled, the connection continues to remain active until the full body is received:

In contrast, the standard IOClient closes the connection when the stream subscription is cancelled. Notice the "Timespan":

[brianquinlan]

Ah, that's interesting. Probably the StreamController i.e. https://github.com/dart-lang/http/blob/63c477b466f650e8f5505d6d78dc283c2c2f9845/pkgs/cronet_http/lib/src/cronet_client.dart#L162C24-L162C40

should handle onCancel and call UrlRequest.cancel