Migrates QUIC sessions to a new network when old network is (about to be) disconnected.

net/quic/quic_connection.cc

Index: net/quic/quic_connection.cc
diff --git a/net/quic/quic_connection.cc b/net/quic/quic_connection.cc
index b2a27d96e19ffde5a758763c5b18a5844d1aa310..cf42259f61747339aaaab4c547457f92713aa682 100644
--- a/net/quic/quic_connection.cc
+++ b/net/quic/quic_connection.cc
@@ -152,7 +152,7 @@ class PingAlarm : public QuicAlarm::Delegate {
   explicit PingAlarm(QuicConnection* connection) : connection_(connection) {}
 
   QuicTime OnAlarm() override {
-    connection_->SendPing();
+    connection_->SendPing(false);
     return QuicTime::Zero();
   }
 
@@ -1806,8 +1806,8 @@ PeerAddressChangeType QuicConnection::DeterminePeerAddressChangeType() {
   return UNKNOWN;
 }
 
-void QuicConnection::SendPing() {
-  if (retransmission_alarm_->IsSet()) {
+void QuicConnection::SendPing(bool force) {
+  if (!force && retransmission_alarm_->IsSet()) {
     return;
   }
   packet_generator_.AddControlFrame(QuicFrame(QuicPingFrame()));