Clean up abs-send-time for audio.

webrtc/voice_engine/voe_rtp_rtcp_impl.h

Index: webrtc/voice_engine/voe_rtp_rtcp_impl.h
diff --git a/webrtc/voice_engine/voe_rtp_rtcp_impl.h b/webrtc/voice_engine/voe_rtp_rtcp_impl.h
index c1e84849b940d7d2e639bfa1844a9cac2db600c7..dcf28410a17fca9ae2f6ce751f7dba0a94850839 100644
--- a/webrtc/voice_engine/voe_rtp_rtcp_impl.h
+++ b/webrtc/voice_engine/voe_rtp_rtcp_impl.h
@@ -51,14 +51,6 @@ class VoERTP_RTCPImpl : public VoERTP_RTCP {
                                            bool enable,
                                            unsigned char id) override;
 
-  // RTP Header Extension for Absolute Sender Time
-  int SetSendAbsoluteSenderTimeStatus(int channel,
-                                      bool enable,
-                                      unsigned char id) override;
-  int SetReceiveAbsoluteSenderTimeStatus(int channel,
-                                         bool enable,
-                                         unsigned char id) override;
-
   // Statistics
   int GetRTPStatistics(int channel,
                        unsigned int& averageJitterMs,