Remove instant_saturating_sub fn in favor of Instant::saturating_duration_since

Author: matheus23

quinn-proto/src/connection/mod.rs

@@ -1523,7 +1523,7 @@ impl Connection {
                     Duration::from_micros(ack.delay << self.peer_params.ack_delay_exponent.0),
                 )
             };
-            let rtt = instant_saturating_sub(now, self.spaces[space].largest_acked_packet_sent);
+            let rtt = now.saturating_duration_since(self.spaces[space].largest_acked_packet_sent);
             self.path.rtt.update(ack_delay, rtt);
             if self.path.first_packet_after_rtt_sample.is_none() {
                 self.path.first_packet_after_rtt_sample =
@@ -4056,10 +4056,6 @@ pub enum Event {
     DatagramsUnblocked,
 }
 
-fn instant_saturating_sub(x: Instant, y: Instant) -> Duration {
-    if x > y { x - y } else { Duration::ZERO }
-}
-
 fn get_max_ack_delay(params: &TransportParameters) -> Duration {
     Duration::from_micros(params.max_ack_delay.0 * 1000)
 }