Change the wire format of the ack frame to include a compressed version

net/quic/quic_received_packet_manager.cc

Index: net/quic/quic_received_packet_manager.cc
diff --git a/net/quic/quic_received_packet_manager.cc b/net/quic/quic_received_packet_manager.cc
index 15030a4e5d9ab79b544ffb3d1f8f69b69bdc82f0..98136f8564f35a70333dbbb705292df9ad667848 100644
--- a/net/quic/quic_received_packet_manager.cc
+++ b/net/quic/quic_received_packet_manager.cc
@@ -7,11 +7,13 @@
 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "net/base/linked_hash_map.h"
+#include "net/quic/crypto/crypto_protocol.h"
 #include "net/quic/quic_connection_stats.h"
 
 using std::make_pair;
 using std::max;
 using std::min;
+using std::numeric_limits;
 
 namespace net {
 
@@ -128,11 +130,10 @@ AdvanceFirstGapAndGarbageCollectEntropyMap() {
 }
 
 QuicReceivedPacketManager::QuicReceivedPacketManager(
-    CongestionFeedbackType congestion_type,
     QuicConnectionStats* stats)
     : peer_least_packet_awaiting_ack_(0),
       time_largest_observed_(QuicTime::Zero()),
-      receive_algorithm_(ReceiveAlgorithmInterface::Create(congestion_type)),
+      receive_algorithm_(ReceiveAlgorithmInterface::Create(kTCP)),
       stats_(stats) {
   ack_frame_.largest_observed = 0;
   ack_frame_.entropy_hash = 0;
@@ -178,6 +179,9 @@ void QuicReceivedPacketManager::RecordPacketReceived(
   receive_algorithm_->RecordIncomingPacket(
       bytes, sequence_number, receipt_time);
 
+  received_packet_times_.push_back(
+      std::make_pair(sequence_number, receipt_time));
+
   ack_frame_.revived_packets.erase(sequence_number);
 }
 
@@ -216,6 +220,15 @@ void QuicReceivedPacketManager::UpdateReceivedPacketInfo(
 
   ack_frame->delta_time_largest_observed =
       approximate_now.Subtract(time_largest_observed_);
+
+  // Remove all packets that are too far from largest_observed to express.
+  received_packet_times_.remove_if(
+      [this] (std::pair<QuicPacketSequenceNumber, QuicTime> p)
+      { return ack_frame_.largest_observed - p.first >=
+        numeric_limits<uint8>::max();});
+
+  ack_frame->received_packet_times = received_packet_times_;
+  received_packet_times_.clear();
 }
 
 bool QuicReceivedPacketManager::GenerateCongestionFeedback(