- BaseRequest request
Sends an HTTP request and asynchronously returns the response.
Implementers should call BaseRequest.finalize to get the body of the request as a ByteStream. They shouldn't make any assumptions about the state of the stream; it could have data written to it asynchronously at a later point, or it could already be closed when it's returned. Any internal HTTP errors should be wrapped as ClientExceptions.
@override Future<StreamedResponse> send(BaseRequest request);