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

webrtc/modules/audio_coding/BUILD.gn

 # Copyright (c) 2014 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.
 
 import("//build/config/arm.gni")
 import("../../build/webrtc.gni")
@@ skipping 795 matching lines @@
     "neteq/dsp_helper.h",
     "neteq/dtmf_buffer.cc",
     "neteq/dtmf_buffer.h",
     "neteq/dtmf_tone_generator.cc",
     "neteq/dtmf_tone_generator.h",
     "neteq/expand.cc",
     "neteq/expand.h",
     "neteq/include/neteq.h",
     "neteq/merge.cc",
     "neteq/merge.h",
-    "neteq/nack.cc",
-    "neteq/nack.h",
+    "neteq/nack_tracker.cc",
+    "neteq/nack_tracker.h",
     "neteq/neteq.cc",
     "neteq/neteq_impl.cc",
     "neteq/neteq_impl.h",
     "neteq/normal.cc",
     "neteq/normal.h",
     "neteq/packet.cc",
     "neteq/packet.h",
     "neteq/packet_buffer.cc",
     "neteq/packet_buffer.h",
     "neteq/payload_splitter.cc",
@@ skipping 52 matching lines @@
       defines += [ "WEBRTC_CODEC_ISACFX" ]
       deps += [ ":isac_fix" ]
     } else {
       defines += [ "WEBRTC_CODEC_ISAC" ]
       deps += [ ":isac" ]
     }
     defines += [ "WEBRTC_CODEC_G722" ]
     deps += [ ":g722" ]
   }
 }