Remove stats for recording reno vs cubic mode in internal server's varz.

net/quic/congestion_control/tcp_cubic_sender.cc

Index: net/quic/congestion_control/tcp_cubic_sender.cc
diff --git a/net/quic/congestion_control/tcp_cubic_sender.cc b/net/quic/congestion_control/tcp_cubic_sender.cc
index 8abedc827ed64157eb2ee40a1d9fa62cc0255b99..4de453eec338419d70979d47ac840c589341579b 100644
--- a/net/quic/congestion_control/tcp_cubic_sender.cc
+++ b/net/quic/congestion_control/tcp_cubic_sender.cc
@@ -34,7 +34,7 @@ TcpCubicSender::TcpCubicSender(const QuicClock* clock,
                                QuicPacketCount max_tcp_congestion_window,
                                QuicConnectionStats* stats)
     : hybrid_slow_start_(clock),
-      cubic_(clock, stats),
+      cubic_(clock),
       rtt_stats_(rtt_stats),
       stats_(stats),
       reno_(reno),
@@ -49,7 +49,8 @@ TcpCubicSender::TcpCubicSender(const QuicClock* clock,
       previous_slowstart_threshold_(0),
       last_cutback_exited_slowstart_(false),
       max_tcp_congestion_window_(max_tcp_congestion_window),
-      clock_(clock) {}
+      clock_(clock) {
+}
 
 TcpCubicSender::~TcpCubicSender() {
   UMA_HISTOGRAM_COUNTS("Net.QuicSession.FinalTcpCwnd", congestion_window_);