Convert channel counts to size_t.

webrtc/modules/audio_coding/codecs/red/audio_encoder_copy_red.cc

 /*
  *  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.
  */
 
@@ skipping 14 matching lines @@
 AudioEncoderCopyRed::~AudioEncoderCopyRed() = default;
 
 size_t AudioEncoderCopyRed::MaxEncodedBytes() const {
   return 2 * speech_encoder_->MaxEncodedBytes();
 }
 
 int AudioEncoderCopyRed::SampleRateHz() const {
   return speech_encoder_->SampleRateHz();
 }
 
-int AudioEncoderCopyRed::NumChannels() const {
+size_t AudioEncoderCopyRed::NumChannels() const {
   return speech_encoder_->NumChannels();
 }
 
 int AudioEncoderCopyRed::RtpTimestampRateHz() const {
   return speech_encoder_->RtpTimestampRateHz();
 }
 
 size_t AudioEncoderCopyRed::Num10MsFramesInNextPacket() const {
   return speech_encoder_->Num10MsFramesInNextPacket();
 }
@@ skipping 68 matching lines @@
 
 void AudioEncoderCopyRed::SetProjectedPacketLossRate(double fraction) {
   speech_encoder_->SetProjectedPacketLossRate(fraction);
 }
 
 void AudioEncoderCopyRed::SetTargetBitrate(int bits_per_second) {
   speech_encoder_->SetTargetBitrate(bits_per_second);
 }
 
 }  // namespace webrtc