Land Recent QUIC Changes.

net/quic/quic_sent_packet_manager.h

Index: net/quic/quic_sent_packet_manager.h
diff --git a/net/quic/quic_sent_packet_manager.h b/net/quic/quic_sent_packet_manager.h
index cf4edc9c53d452b32ae0eb6959f2b0bdcdf30ae3..e6878dddff86060804f85ae41c11bd11c92f6f5d 100644
--- a/net/quic/quic_sent_packet_manager.h
+++ b/net/quic/quic_sent_packet_manager.h
@@ -92,11 +92,6 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
   // Returns true if |sequence_number| is a retransmission of a packet.
   bool IsRetransmission(QuicPacketSequenceNumber sequence_number) const;
 
-  // Returns the number of times the data in the packet |sequence_number|
-  // has been transmitted.
-  size_t GetRetransmissionCount(
-      QuicPacketSequenceNumber sequence_number) const;
-
   // Returns true if the non-FEC packet |sequence_number| is unacked.
   bool IsUnacked(QuicPacketSequenceNumber sequence_number) const;
 
@@ -131,8 +126,8 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
   // Returns true if there are any unacked packets.
   bool HasUnackedPackets() const;
 
-  // Returns the number of unacked packets.
-  size_t GetNumUnackedPackets() const;
+  // Returns the number of unacked packets which have retransmittable frames.
+  size_t GetNumRetransmittablePackets() const;
 
   // Returns true if there are any unacked FEC packets.
   bool HasUnackedFecPackets() const;
@@ -155,32 +150,25 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
   bool IsPreviousTransmission(QuicPacketSequenceNumber sequence_number) const;
 
  private:
-  struct RetransmissionInfo {
-    RetransmissionInfo() {}
-    explicit RetransmissionInfo(QuicPacketSequenceNumber sequence_number,
-                                QuicSequenceNumberLength sequence_number_length)
-        : sequence_number(sequence_number),
-          sequence_number_length(sequence_number_length),
-          number_nacks(0),
-          number_retransmissions(0) {
+  struct TransmissionInfo {
+    TransmissionInfo() {}
+    TransmissionInfo(RetransmittableFrames* retransmittable_frames,
+                     QuicSequenceNumberLength sequence_number_length)
+        : retransmittable_frames(retransmittable_frames),
+          sequence_number_length(sequence_number_length) {
     }
 
-    QuicPacketSequenceNumber sequence_number;
+    RetransmittableFrames* retransmittable_frames;
     QuicSequenceNumberLength sequence_number_length;
-    size_t number_nacks;
-    // TODO(ianswett): I believe this is now obsolete, or could at least be
-    // changed to a bool.
-    size_t number_retransmissions;
   };
 
   typedef linked_hash_map<QuicPacketSequenceNumber,
-                          RetransmittableFrames*> UnackedPacketMap;
+                          TransmissionInfo> UnackedPacketMap;
   typedef linked_hash_map<QuicPacketSequenceNumber,
                           QuicTime> UnackedFecPacketMap;
   typedef linked_hash_map<QuicPacketSequenceNumber,
                           TransmissionType> PendingRetransmissionMap;
-  typedef base::hash_map<QuicPacketSequenceNumber,
-                         RetransmissionInfo> RetransmissionMap;
+  typedef base::hash_map<QuicPacketSequenceNumber, size_t> NackMap;
   typedef base::hash_map<QuicPacketSequenceNumber, SequenceNumberSet*>
                          PreviousTransmissionMap;
 
@@ -228,10 +216,9 @@ class NET_EXPORT_PRIVATE QuicSentPacketManager {
   // Pending retransmissions which have not been packetized and sent yet.
   PendingRetransmissionMap pending_retransmissions_;
 
-  // Map from sequence number to the retransmission info for a packet.
-  // This includes the retransmission timeout, and the NACK count.  Only
-  // the new transmission of a packet will have entries in this map.
-  RetransmissionMap retransmission_map_;
+  // Map from sequence number to the number of nacks for the packet.
+  // Only the most recent transmission of packets are present in this map.
+  NackMap nack_map_;
 
   // Map from sequence number to set of all sequence number that this packet has
   // been transmitted as.  If a packet has not been retransmitted, it will not