Moved codec-specific audio packet splitting into decoders.

webrtc/modules/audio_coding/codecs/g711/audio_decoder_pcm.h

Index: webrtc/modules/audio_coding/codecs/g711/audio_decoder_pcm.h
diff --git a/webrtc/modules/audio_coding/codecs/g711/audio_decoder_pcm.h b/webrtc/modules/audio_coding/codecs/g711/audio_decoder_pcm.h
index 7fdc3591b309c6ce1638cb6b05fc2ab7d74988e0..33a2933a7738a16550b19d0c489666446bd6d486 100644
--- a/webrtc/modules/audio_coding/codecs/g711/audio_decoder_pcm.h
+++ b/webrtc/modules/audio_coding/codecs/g711/audio_decoder_pcm.h
@@ -23,6 +23,8 @@ class AudioDecoderPcmU final : public AudioDecoder {
     RTC_DCHECK_GE(num_channels, 1u);
   }
   void Reset() override;
+  std::vector<PacketSplit> SplitPacket(
+      rtc::ArrayView<const uint8_t> payload) const override;
   int PacketDuration(const uint8_t* encoded, size_t encoded_len) const override;
   int SampleRateHz() const override;
   size_t Channels() const override;
@@ -45,6 +47,8 @@ class AudioDecoderPcmA final : public AudioDecoder {
     RTC_DCHECK_GE(num_channels, 1u);
   }
   void Reset() override;
+  std::vector<PacketSplit> SplitPacket(
+      rtc::ArrayView<const uint8_t> payload) const override;
   int PacketDuration(const uint8_t* encoded, size_t encoded_len) const override;
   int SampleRateHz() const override;
   size_t Channels() const override;