Add a PacketOptions struct to webrtc::Transport.

webrtc/modules/rtp_rtcp/source/nack_rtx_unittest.cc

Index: webrtc/modules/rtp_rtcp/source/nack_rtx_unittest.cc
diff --git a/webrtc/modules/rtp_rtcp/source/nack_rtx_unittest.cc b/webrtc/modules/rtp_rtcp/source/nack_rtx_unittest.cc
index 6f13056f5f45ac32714f833e1efc0e0f19170635..c8140e94c980459a1e7ad35e0a214410e3c201ad 100644
--- a/webrtc/modules/rtp_rtcp/source/nack_rtx_unittest.cc
+++ b/webrtc/modules/rtp_rtcp/source/nack_rtx_unittest.cc
@@ -96,7 +96,9 @@ class RtxLoopBackTransport : public webrtc::Transport {
     packet_loss_ = 0;
   }
 
-  bool SendRtp(const uint8_t* data, size_t len) override {
+  bool SendRtp(const uint8_t* data,
+               size_t len,
+               const PacketOptions& options) override {
     count_++;
     const unsigned char* ptr = static_cast<const unsigned  char*>(data);
     uint32_t ssrc = (ptr[8] << 24) + (ptr[9] << 16) + (ptr[10] << 8) + ptr[11];