Change GetLeastUnacked() to return the next packet that could be sent

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 6ea49a3c83030e9c433bd54ca6c1db373652133f..f84d08c9eace955fffe66eb7cb543f0d9a53025c 100644
--- a/net/quic/quic_connection.cc
+++ b/net/quic/quic_connection.cc
@@ -933,9 +933,7 @@ void QuicConnection::UpdateStopWaitingCount() {
 }
 
 QuicPacketSequenceNumber QuicConnection::GetLeastUnacked() const {
-  return sent_packet_manager_.HasUnackedPackets() ?
-      sent_packet_manager_.GetLeastUnackedSentPacket() :
-      packet_generator_.sequence_number() + 1;
+  return sent_packet_manager_.GetLeastUnacked();
 }
 
 void QuicConnection::MaybeSendInResponseToPacket() {