Update from https://crrev.com/309415

net/quic/crypto/cached_network_parameters.h

Index: net/quic/crypto/cached_network_parameters.h
diff --git a/net/quic/crypto/cached_network_parameters.h b/net/quic/crypto/cached_network_parameters.h
index 5f22070dc4f75f8156916dfdf1aedb11ac2d842f..34c89171897eb48ee3ae4ce93e7b409edcd53546 100644
--- a/net/quic/crypto/cached_network_parameters.h
+++ b/net/quic/crypto/cached_network_parameters.h
@@ -68,7 +68,9 @@ class NET_EXPORT_PRIVATE CachedNetworkParameters {
   }
   void set_min_rtt_ms(int32 min_rtt_ms) {
     min_rtt_ms_ = min_rtt_ms;
+    has_min_rtt_ms_ = true;
   }
+  bool has_min_rtt_ms() const { return has_min_rtt_ms_; }
 
   int32 previous_connection_state() const {
     return previous_connection_state_;
@@ -98,6 +100,8 @@ class NET_EXPORT_PRIVATE CachedNetworkParameters {
   // The min RTT seen on a previous connection can be used by the server to
   // inform initial connection parameters for new connections.
   int32 min_rtt_ms_;
+  // Whenever min_rtt_ms_ is updated, it is set to true.
+  bool has_min_rtt_ms_;
   // Encodes the PreviousConnectionState enum.
   int32 previous_connection_state_;
   // UNIX timestamp when this bandwidth estimate was created.