Refactor of QUIC's rtt storage and calculation to have a single RttStats

net/quic/congestion_control/send_algorithm_interface.h

Index: net/quic/congestion_control/send_algorithm_interface.h
diff --git a/net/quic/congestion_control/send_algorithm_interface.h b/net/quic/congestion_control/send_algorithm_interface.h
index 359c65c61d91d3b48f82f579c0adaa95ebb92180..afd52580a104d18eb789caa9595f8db7b34a604a 100644
--- a/net/quic/congestion_control/send_algorithm_interface.h
+++ b/net/quic/congestion_control/send_algorithm_interface.h
@@ -21,9 +21,12 @@
 
 namespace net {
 
+class RttStats;
+
 class NET_EXPORT_PRIVATE SendAlgorithmInterface {
  public:
   static SendAlgorithmInterface* Create(const QuicClock* clock,
+                                        const RttStats* rtt_stats,
                                         CongestionFeedbackType type,
                                         QuicConnectionStats* stats);
 
@@ -76,11 +79,10 @@ class NET_EXPORT_PRIVATE SendAlgorithmInterface {
   virtual QuicBandwidth BandwidthEstimate() const = 0;
 
   // Updates the smoothed RTT based on a new sample.
+  // TODO(ianswett): Now that the RTT is managed by RTTStats, it may be
+  // possible to remove this method.
   virtual void UpdateRtt(QuicTime::Delta rtt_sample) = 0;
 
-  // TODO(satyamshekhar): Monitor MinRtt.
-  virtual QuicTime::Delta SmoothedRtt() const = 0;
-
   // Get the send algorithm specific retransmission delay, called RTO in TCP,
   // Note 1: the caller is responsible for sanity checking this value.
   // Note 2: this will return zero if we don't have enough data for an estimate.