Remove dual stream functionality in VoiceEngine

This is old code that is no longer in use. The clean-up is part of the
ACM redesign work. The corresponding code in ACM will be deleted in a
follow-up CL.

BUG=3520
R=henrika@webrtc.org, pbos@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/32999004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@8060 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/voice_engine/voe_codec_impl.h

@@ -56,14 +56,6 @@ public:
 
     virtual int SetOpusMaxPlaybackRate(int channel, int frequency_hz);
 
-    // Dual-streaming
-    virtual int SetSecondarySendCodec(int channel, const CodecInst& codec,
-                                      int red_payload_type);
-
-    virtual int RemoveSecondarySendCodec(int channel);
-
-    virtual int GetSecondarySendCodec(int channel, CodecInst& codec);
-
 protected:
     VoECodecImpl(voe::SharedData* shared);
     virtual ~VoECodecImpl();