Fix an implicit narrowing conversion found by MSVC

webrtc/api/audio_codecs/L16/audio_encoder_L16.cc

 /*
  *  Copyright (c) 2017 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/api/audio_codecs/L16/audio_encoder_L16.h"
 
 #include "webrtc/common_types.h"
 #include "webrtc/modules/audio_coding/codecs/pcm16b/audio_encoder_pcm16b.h"
 #include "webrtc/modules/audio_coding/codecs/pcm16b/pcm16b_common.h"
 #include "webrtc/rtc_base/ptr_util.h"

[kwiberg-webrtc, 2017/08/22 20:06:05]

#include safe_conversions.h here?

[oprypin_webrtc, 2017/08/22 20:28:39]

Done in both places

 
 namespace webrtc {
 
 rtc::Optional<AudioEncoderL16::Config> AudioEncoderL16::SdpToConfig(
     const SdpAudioFormat& format) {
   Config config;
   config.sample_rate_hz = format.clockrate_hz;
-  config.num_channels = format.num_channels;
+  config.num_channels = rtc::checked_cast<int>(format.num_channels);
   return STR_CASE_CMP(format.name.c_str(), "L16") == 0 && config.IsOk()
              ? rtc::Optional<Config>(config)
              : rtc::Optional<Config>();
 }
 
 void AudioEncoderL16::AppendSupportedEncoders(
     std::vector<AudioCodecSpec>* specs) {
   Pcm16BAppendSupportedCodecSpecs(specs);
 }
 
@@ skipping 11 matching lines @@
   RTC_DCHECK(config.IsOk());
   AudioEncoderPcm16B::Config c;
   c.sample_rate_hz = config.sample_rate_hz;
   c.num_channels = config.num_channels;
   c.frame_size_ms = config.frame_size_ms;
   c.payload_type = payload_type;
   return rtc::MakeUnique<AudioEncoderPcm16B>(c);
 }
 
 }  // namespace webrtc