Update from https://crrev.com/303153

net/quic/quic_sent_packet_manager.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_QUIC_QUIC_SENT_PACKET_MANAGER_H_
 #define NET_QUIC_QUIC_SENT_PACKET_MANAGER_H_
 
 #include <map>
 #include <set>
 #include <utility>
@@ skipping 164 matching lines @@
   const RttStats* GetRttStats() const;
 
   // Returns the estimated bandwidth calculated by the congestion algorithm.
   QuicBandwidth BandwidthEstimate() const;
 
   // Returns true if the current instantaneous bandwidth estimate is reliable.
   bool HasReliableBandwidthEstimate() const;
 
   const QuicSustainedBandwidthRecorder& SustainedBandwidthRecorder() const;
 
-  // Returns the size of the current congestion window in bytes.  Note, this is
-  // not the *available* window.  Some send algorithms may not use a congestion
-  // window and will return 0.
-  QuicByteCount GetCongestionWindow() const;
+  // Returns the size of the current congestion window in number of
+  // kDefaultTCPMSS-sized segments. Note, this is not the *available* window.
+  // Some send algorithms may not use a congestion window and will return 0.
+  QuicPacketCount GetCongestionWindowInTcpMss() const;
 
-  // Returns the size of the slow start congestion window in bytes,
-  // aka ssthresh.  Some send algorithms do not define a slow start
-  // threshold and will return 0.
-  QuicByteCount GetSlowStartThreshold() const;
+  // Returns the number of packets of length |max_packet_length| which fit in
+  // the current congestion window. More packets may end up in flight if the
+  // congestion window has been recently reduced, of if non-full packets are
+  // sent.
+  QuicPacketCount EstimateMaxPacketsInFlight(
+      QuicByteCount max_packet_length) const;
+
+  // Returns the size of the slow start congestion window in nume of 1460 byte
+  // TCP segments, aka ssthresh.  Some send algorithms do not define a slow
+  // start threshold and will return 0.
+  QuicPacketCount GetSlowStartThresholdInTcpMss() const;
 
   // Enables pacing if it has not already been enabled.
   void EnablePacing();
 
   bool using_pacing() const { return using_pacing_; }
 
   void set_debug_delegate(DebugDelegate* debug_delegate) {
     debug_delegate_ = debug_delegate;
   }
 
@@ skipping 179 matching lines @@
   // Records bandwidth from server to client in normal operation, over periods
   // of time with no loss events.
   QuicSustainedBandwidthRecorder sustained_bandwidth_recorder_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicSentPacketManager);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_SENT_PACKET_MANAGER_H_