Deprecate FLAGS_quic_reloadable_flag_quic_bbr_ack_spacing2 in the disabled position because it neve…

net/quic/core/congestion_control/bbr_sender.h

Index: net/quic/core/congestion_control/bbr_sender.h
diff --git a/net/quic/core/congestion_control/bbr_sender.h b/net/quic/core/congestion_control/bbr_sender.h
index 421f625f6f6ab6fb3f1949b9a8f646396f8bc8a7..9a6cd7e388c7666f9caa2e5a7b8ef7754c1f3b88 100644
--- a/net/quic/core/congestion_control/bbr_sender.h
+++ b/net/quic/core/congestion_control/bbr_sender.h
@@ -196,11 +196,6 @@ class QUIC_EXPORT_PRIVATE BbrSender : public SendAlgorithmInterface {
                            bool has_losses,
                            bool is_round_start);
 
-  // Updates the ack spacing max filter if a larger value is observed.
-  void UpdateAckSpacing(QuicTime ack_time,
-                        QuicPacketNumber largest_newly_acked,
-                        const CongestionVector& acked_packets);
-
   // Updates the ack aggregation max filter in bytes.
   void UpdateAckAggregationBytes(QuicTime ack_time,
                                  QuicByteCount newly_acked_bytes);
@@ -236,13 +231,6 @@ class QUIC_EXPORT_PRIVATE BbrSender : public SendAlgorithmInterface {
   // round-trips.
   MaxBandwidthFilter max_bandwidth_;
 
-  // Tracks the maximum spacing between two acks acknowledging in order packets.
-  MaxAckDelayFilter max_ack_spacing_;
-
-  // The time the largest acked packet was acked and when it was sent.
-  QuicTime largest_acked_time_;
-  QuicTime largest_acked_sent_time_;
-
   // Tracks the maximum number of bytes acked faster than the sending rate.
   MaxAckHeightFilter max_ack_height_;