Update from chromium https://crrev.com/302282

net/quic/congestion_control/tcp_loss_algorithm.cc

Index: net/quic/congestion_control/tcp_loss_algorithm.cc
diff --git a/net/quic/congestion_control/tcp_loss_algorithm.cc b/net/quic/congestion_control/tcp_loss_algorithm.cc
index b0a5a15b4972fa0baacaf34e3638c9fab3502587..e609122dea5b7fc907b162f77bf27aa42f79f006 100644
--- a/net/quic/congestion_control/tcp_loss_algorithm.cc
+++ b/net/quic/congestion_control/tcp_loss_algorithm.cc
@@ -10,14 +10,9 @@
 namespace net {
 
 namespace {
-
-// TCP retransmits after 3 nacks.
-static const size_t kNumberOfNacksBeforeRetransmission = 3;
-
 // How many RTTs the algorithm waits before determining a packet is lost due
 // to early retransmission.
 static const double kEarlyRetransmitLossDelayMultiplier = 1.25;
-
 }
 
 TCPLossAlgorithm::TCPLossAlgorithm()