WebRtcVoiceEngine: Use AudioDecoderFactory to generate recv codecs.

webrtc/modules/audio_coding/codecs/builtin_audio_decoder_factory.cc

 /*
  *  Copyright (c) 2016 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 112 matching lines @@
                       num_channels
                   ? Unique(new AudioDecoderOpus(*num_channels))
                   : nullptr;
      }},
 #endif
 };
 
 class BuiltinAudioDecoderFactory : public AudioDecoderFactory {
  public:
   std::vector<SdpAudioFormat> GetSupportedFormats() override {
-    FATAL() << "Not implemented yet!";
+    static std::vector<SdpAudioFormat> formats = {
+      { "opus", 48000, 2, {
+          {"minptime", "10" },
+          {"useinbandfec", "1" }
+        }
+      },
+      { "isac", 16000, 1 },
+      { "isac", 32000, 1 },
+      { "G722", 8000,  1 },
+      { "iLBC", 8000,  1 },
+      { "PCMU", 8000,  1 },
+      { "PCMA", 8000,  1 }
+    };
+
+    return formats;
   }
 
   std::unique_ptr<AudioDecoder> MakeAudioDecoder(
       const SdpAudioFormat& format) override {
     for (const auto& dc : decoder_constructors) {
       if (STR_CASE_CMP(format.name.c_str(), dc.name) == 0) {
         std::unique_ptr<AudioDecoder> dec = dc.constructor(format);
         if (dec) {
           const int expected_sample_rate_hz =
               STR_CASE_CMP(format.name.c_str(), "g722") == 0
                   ? 2 * format.clockrate_hz
                   : format.clockrate_hz;
           RTC_CHECK_EQ(expected_sample_rate_hz, dec->SampleRateHz());
         }
         return dec;
       }
     }
     return nullptr;
   }
 };
 
 }  // namespace
 
 rtc::scoped_refptr<AudioDecoderFactory> CreateBuiltinAudioDecoderFactory() {
   return rtc::scoped_refptr<AudioDecoderFactory>(
       new rtc::RefCountedObject<BuiltinAudioDecoderFactory>);
 }
 
 }  // namespace webrtc