Convert channel counts to size_t.

webrtc/modules/audio_coding/codecs/opus/audio_decoder_opus.cc

 /*
  *  Copyright (c) 2015 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.
  */
 
 #include "webrtc/modules/audio_coding/codecs/opus/audio_decoder_opus.h"
 
 #include "webrtc/base/checks.h"
 
 namespace webrtc {
 
 AudioDecoderOpus::AudioDecoderOpus(size_t num_channels)
     : channels_(num_channels) {
   RTC_DCHECK(num_channels == 1 || num_channels == 2);
-  WebRtcOpus_DecoderCreate(&dec_state_, static_cast<int>(channels_));
+  WebRtcOpus_DecoderCreate(&dec_state_, channels_);
   WebRtcOpus_DecoderInit(dec_state_);
 }
 
 AudioDecoderOpus::~AudioDecoderOpus() {
   WebRtcOpus_DecoderFree(dec_state_);
 }
 
 int AudioDecoderOpus::DecodeInternal(const uint8_t* encoded,
                                      size_t encoded_len,
                                      int sample_rate_hz,
@@ skipping 54 matching lines @@
   int fec;
   fec = WebRtcOpus_PacketHasFec(encoded, encoded_len);
   return (fec == 1);
 }
 
 size_t AudioDecoderOpus::Channels() const {
   return channels_;
 }
 
 }  // namespace webrtc