Remove unused histograms: Net.QuicSession.21* & Net.QuicSession.6*

net/quic/quic_connection_logger.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_QUIC_QUIC_CONNECTION_LOGGER_H_
 #define NET_QUIC_QUIC_CONNECTION_LOGGER_H_
 
 #include <stddef.h>
 
 #include <bitset>
@@ skipping 76 matching lines @@
 
  private:
   friend class test::QuicConnectionLoggerPeer;
 
   // Do a factory get for a histogram for recording data, about individual
   // packet numbers, that was gathered in the vectors
   // received_packets_ and received_acks_. |statistic_name| identifies which
   // element of data is recorded, and is used to form the histogram name.
   base::HistogramBase* GetPacketNumberHistogram(
       const char* statistic_name) const;
-  // Do a factory get for a histogram to record a 6-packet loss-sequence as a
-  // sample. The histogram will record the 64 distinct possible combinations.
-  // |which_6| is used to adjust the name of the histogram to distinguish the
-  // first 6 packets in a connection, vs. some later 6 packets.
-  base::HistogramBase* Get6PacketHistogram(const char* which_6) const;
-  // Do a factory get for a histogram to record cumulative stats across a 21
-  // packet sequence.  |which_21| is used to adjust the name of the histogram
-  // to distinguish the first 21 packets' loss data, vs. some later 21 packet
-  // sequences' loss data.
-  base::HistogramBase* Get21CumulativeHistogram(const char* which_21) const;
-  // Add samples associated with a |bit_mask_of_packets| to the given histogram
-  // that was provided by Get21CumulativeHistogram().  The LSB of that mask
-  // corresponds to the oldest packet number in the series of packets,
-  // and the bit in the 2^20 position corresponds to the most recently received
-  // packet.  Of the maximum of 21 bits that are valid (correspond to packets),
-  // only the most significant |valid_bits_in_mask| are processed.
-  // A bit value of 0 indicates that a packet was never received, and a 1
-  // indicates the packet was received.
-  static void AddTo21CumulativeHistogram(base::HistogramBase* histogram,
-                                         int bit_mask_of_packets,
-                                         int valid_bits_in_mask);
   // For connections longer than 21 received packets, this call will calculate
   // the overall packet loss rate, and record it into a histogram.
   void RecordAggregatePacketLossRate() const;
   // At destruction time, this records results of |pacaket_received_| into
   // histograms for specific connection types.
   void RecordLossHistograms() const;
 
   BoundNetLog net_log_;
   QuicSpdySession* session_;  // Unowned.
   // The last packet number received.
@@ skipping 58 matching lines @@
   // Receives notifications regarding the performance of the underlying socket
   // for the QUIC connection. May be null.
   const scoped_ptr<SocketPerformanceWatcher> socket_performance_watcher_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicConnectionLogger);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_CONNECTION_LOGGER_H_