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

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 187f8e004e7670a00ed6caa99492d25bd5e734f7..e8be74a4e7b874848763540ee350acdef6893b8a 100644
--- a/net/quic/quic_received_packet_manager.cc
+++ b/net/quic/quic_received_packet_manager.cc
@@ -284,10 +284,14 @@ void QuicReceivedPacketManager::UpdatePacketInformationSentByPeer(
              peer_least_packet_awaiting_ack_);
 }
 
-bool QuicReceivedPacketManager::HasNewMissingPackets() {
+bool QuicReceivedPacketManager::HasNewMissingPackets() const {
   return !ack_frame_.missing_packets.empty() &&
       (ack_frame_.largest_observed -
        *ack_frame_.missing_packets.rbegin()) <= kMaxPacketsAfterNewMissing;
 }
 
+size_t QuicReceivedPacketManager::NumTrackedPackets() const {
+  return entropy_tracker_.size();
+}
+
 }  // namespace net