Review and possibly remove legacy consumer-buffer logic in PassiveStream::streamEnd

    if (res == cb::engine_errc::success) {

        // Stream End message successfully passed to stream. Can now remove

        // the stream from the streams map as it has completed its lifetime.

        removeStream(vbucket);

        // @todo MB-60438: Review and possibly remove

        // Note we are potentially racing with the consumer buffering task

        // which may call setDead, so we don't call setDead here (that could be

        // state transition violation/exception), hence we just move out the

        // flow control bytes (could be 0) and ensure they are accounted for.

        flowControl.incrFreedBytes(stream->moveFlowControlBytes());

    }