Initial asymmetric codec support in MediaSessionDescription

webrtc/pc/mediasession.h

Index: webrtc/pc/mediasession.h
diff --git a/webrtc/pc/mediasession.h b/webrtc/pc/mediasession.h
index 39ac26bd8dad104c5b10b0d450caf7cf67e85233..a4e78bd6597a2f8c8e6e01208cc372c80d130886 100644
--- a/webrtc/pc/mediasession.h
+++ b/webrtc/pc/mediasession.h
@@ -52,6 +52,8 @@ enum MediaContentDirection {
   MD_SENDRECV
 };
 
+std::string MediaContentDirectionToString(MediaContentDirection direction);
+
 enum CryptoType {
   CT_NONE,
   CT_SDES,
@@ -395,8 +397,12 @@ class MediaSessionDescriptionFactory {
   MediaSessionDescriptionFactory(ChannelManager* cmanager,
                                  const TransportDescriptionFactory* factory);
 
-  const AudioCodecs& audio_codecs() const { return audio_codecs_; }
-  void set_audio_codecs(const AudioCodecs& codecs) { audio_codecs_ = codecs; }
+  const AudioCodecs& audio_codecs() const;
+  const AudioCodecs& audio_send_codecs() const;
+  const AudioCodecs& audio_recv_codecs() const;
+  void set_audio_codecs(const AudioCodecs& send_and_recv_codecs);
+  void set_audio_codecs(const AudioCodecs& send_codecs,
+                        const AudioCodecs& recv_codecs);
   void set_audio_rtp_header_extensions(const RtpHeaderExtensions& extensions) {
     audio_rtp_extensions_ = extensions;
   }
@@ -431,6 +437,9 @@ class MediaSessionDescriptionFactory {
 
  private:
   void GetCodecsToOffer(const SessionDescription* current_description,
+                        const AudioCodecs& supported_audio_codecs,
+                        const VideoCodecs& supported_video_codecs,
+                        const DataCodecs& supported_data_codecs,
                         AudioCodecs* audio_codecs,
                         VideoCodecs* video_codecs,
                         DataCodecs* data_codecs) const;
@@ -502,7 +511,9 @@ class MediaSessionDescriptionFactory {
       StreamParamsVec* current_streams,
       SessionDescription* answer) const;
 
-  AudioCodecs audio_codecs_;
+  AudioCodecs audio_send_codecs_;
+  AudioCodecs audio_recv_codecs_;
+  AudioCodecs audio_sendrecv_codecs_;
   RtpHeaderExtensions audio_rtp_extensions_;
   VideoCodecs video_codecs_;
   RtpHeaderExtensions video_rtp_extensions_;