Make rtcp sender use max transfer unit.

webrtc/modules/rtp_rtcp/source/rtp_sender.h

Index: webrtc/modules/rtp_rtcp/source/rtp_sender.h
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_sender.h b/webrtc/modules/rtp_rtcp/source/rtp_sender.h
index b376c380d05919af17a8107be25eb665a27020a8..4344df67451a28f411fc60ed0a71a261523e3e51 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_sender.h
+++ b/webrtc/modules/rtp_rtcp/source/rtp_sender.h
@@ -67,7 +67,6 @@ class RTPSenderInterface {
   virtual uint16_t SequenceNumber() const = 0;
   virtual size_t MaxPayloadLength() const = 0;
   virtual size_t MaxDataPayloadLength() const = 0;
-  virtual uint16_t PacketOverHead() const = 0;
   virtual uint16_t ActualSendBitrateKbit() const = 0;
 
   virtual int32_t SendToNetwork(uint8_t* data_buffer,
@@ -146,7 +145,7 @@ class RTPSender : public RTPSenderInterface {
 
   void SetCsrcs(const std::vector<uint32_t>& csrcs);
 
-  int32_t SetMaxPayloadLength(size_t length, uint16_t packet_over_head);
+  void SetMaxPayloadLength(size_t max_payload_length);
 
   int32_t SendOutgoingData(FrameType frame_type,
                            int8_t payload_type,
@@ -247,7 +246,6 @@ class RTPSender : public RTPSenderInterface {
   size_t RTPHeaderLength() const override;
   uint16_t AllocateSequenceNumber(uint16_t packets_to_send) override;
   size_t MaxPayloadLength() const override;
-  uint16_t PacketOverHead() const override;
 
   // Current timestamp.
   uint32_t Timestamp() const override;
@@ -437,7 +435,6 @@ class RTPSender : public RTPSenderInterface {
   bool sending_media_ GUARDED_BY(send_critsect_);
 
   size_t max_payload_length_;
-  uint16_t packet_over_head_;
 
   int8_t payload_type_ GUARDED_BY(send_critsect_);
   std::map<int8_t, RtpUtility::Payload*> payload_type_map_;