NetEq: Rename Nack to NackTracker to avoid name collisions in GN

webrtc/modules/audio_coding/neteq/neteq_impl.h

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 24 matching lines @@
 class BufferLevelFilter;
 class ComfortNoise;
 class DecisionLogic;
 class DecoderDatabase;
 class DelayManager;
 class DelayPeakDetector;
 class DtmfBuffer;
 class DtmfToneGenerator;
 class Expand;
 class Merge;
-class Nack;
+class NackTracker;
 class Normal;
 class PacketBuffer;
 class PayloadSplitter;
 class PostDecodeVad;
 class PreemptiveExpand;
 class RandomVector;
 class SyncBuffer;
 class TimestampScaler;
 struct AccelerateFactory;
 struct DtmfEvent;
@@ skipping 342 matching lines @@
   bool reset_decoder_ GUARDED_BY(crit_sect_);
   uint8_t current_rtp_payload_type_ GUARDED_BY(crit_sect_);
   uint8_t current_cng_rtp_payload_type_ GUARDED_BY(crit_sect_);
   uint32_t ssrc_ GUARDED_BY(crit_sect_);
   bool first_packet_ GUARDED_BY(crit_sect_);
   int error_code_ GUARDED_BY(crit_sect_);  // Store last error code.
   int decoder_error_code_ GUARDED_BY(crit_sect_);
   const BackgroundNoiseMode background_noise_mode_ GUARDED_BY(crit_sect_);
   NetEqPlayoutMode playout_mode_ GUARDED_BY(crit_sect_);
   bool enable_fast_accelerate_ GUARDED_BY(crit_sect_);
-  std::unique_ptr<Nack> nack_ GUARDED_BY(crit_sect_);
+  std::unique_ptr<NackTracker> nack_ GUARDED_BY(crit_sect_);
   bool nack_enabled_ GUARDED_BY(crit_sect_);
   const bool enable_muted_state_ GUARDED_BY(crit_sect_);
   AudioFrame::VADActivity last_vad_activity_ GUARDED_BY(crit_sect_) =
       AudioFrame::kVadPassive;
   std::unique_ptr<TickTimer::Stopwatch> generated_noise_stopwatch_
       GUARDED_BY(crit_sect_);
 
  private:
   RTC_DISALLOW_COPY_AND_ASSIGN(NetEqImpl);
 };
 
 }  // namespace webrtc
 #endif  // WEBRTC_MODULES_AUDIO_CODING_NETEQ_NETEQ_IMPL_H_