message: Implement mt's simple algo
diff: @@ -120,17 +120,15 @@ impl CongestionControl {
  let congestion_period = pto * PERSISTENT_CONG_THRESH;
  - let first_lost_pkt_after_largest_acked = lost_packets
  + // Simpler to ignore any acked pkts in between first and last lost pkts
  + if let Some(first) = lost_packets
  .iter()
  - .find(|pkt| Some(pkt.time_sent) > prev_largest_acked_sent);
  -
  - let starting_time_sent = first_lost_pkt_after_largest_acked
  - .unwrap_or_else(|| lost_packets.first().unwrap())
  - .time_sent;
  -
  - if starting_time_sent < last_lost_pkt.time_sent - congestion_period {
  - qinfo!([self], "persistent congestion");
  + .find(|p| Some(p.time_sent) > prev_largest_acked_sent)
  + {
  + if last_lost_pkt.time_sent.duration_since(first.time_sent) > congestion_period {
  self.congestion_window = MIN_CONG_WINDOW;
  + qinfo!([self], "persistent congestion");
  + }
  }
  }
  