Let AudioCodingModule::SendCodec return Maybe<CodecInst>

webrtc/modules/audio_coding/main/acm2/audio_coding_module_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 30 matching lines @@
   //   Sender
   //
 
   // Can be called multiple times for Codec, CNG, RED.
   int RegisterSendCodec(const CodecInst& send_codec) override;
 
   void RegisterExternalSendCodec(
       AudioEncoder* external_speech_encoder) override;
 
   // Get current send codec.
-  int SendCodec(CodecInst* current_codec) const override;
+  rtc::Maybe<CodecInst> SendCodec() const override;
 
   // Get current send frequency.
   int SendFrequency() const override;
 
   // Sets the bitrate to the specified value in bits/sec. In case the codec does
   // not support the requested value it will choose an appropriate value
   // instead.
   void SetBitRate(int bitrate_bps) override;
 
   // Register a transport callback which will be
@@ skipping 210 matching lines @@
   const rtc::scoped_ptr<CriticalSectionWrapper> callback_crit_sect_;
   AudioPacketizationCallback* packetization_callback_
       GUARDED_BY(callback_crit_sect_);
   ACMVADCallback* vad_callback_ GUARDED_BY(callback_crit_sect_);
 };
 
 }  // namespace acm2
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_CODING_MAIN_ACM2_AUDIO_CODING_MODULE_IMPL_H_