Reset QUIC's retransmission counters whenever a new packet is acked

net/quic/quic_sent_packet_manager_test.cc

Index: net/quic/quic_sent_packet_manager_test.cc
diff --git a/net/quic/quic_sent_packet_manager_test.cc b/net/quic/quic_sent_packet_manager_test.cc
index b0e861d921a8a465a3fec2fe9ecffff1adf15033..5fc074e611561a4dfe4fc339b34fd2db976b5471 100644
--- a/net/quic/quic_sent_packet_manager_test.cc
+++ b/net/quic/quic_sent_packet_manager_test.cc
@@ -1155,6 +1155,15 @@ TEST_F(QuicSentPacketManagerTest, GetTransmissionTimeRTO) {
   // The delay should double the second time.
   expected_time = clock_.Now().Add(expected_rto_delay).Add(expected_rto_delay);
   EXPECT_EQ(expected_time, manager_.GetRetransmissionTime());
+
+  // Ack a packet and ensure the RTO goes back to the original value.
+  ReceivedPacketInfo received_info;
+  received_info.largest_observed = 2;
+  received_info.missing_packets.insert(1);
+  manager_.OnIncomingAck(received_info, QuicTime::Zero());
+
+  expected_time = clock_.Now().Add(expected_rto_delay);
+  EXPECT_EQ(expected_time, manager_.GetRetransmissionTime());
 }
 
 TEST_F(QuicSentPacketManagerTest, GetTransmissionDelayMin) {