Add a PacketOptions struct to webrtc::Transport.

webrtc/test/null_transport.h

Index: webrtc/test/null_transport.h
diff --git a/webrtc/test/null_transport.h b/webrtc/test/null_transport.h
index a60d8cb91e22ce636af991b2c5ee91389d70e367..f4b704634d1c533b7be5a417e05167536a5dabbe 100644
--- a/webrtc/test/null_transport.h
+++ b/webrtc/test/null_transport.h
@@ -19,7 +19,9 @@ class PacketReceiver;
 namespace test {
 class NullTransport : public Transport {
  public:
-  bool SendRtp(const uint8_t* packet, size_t length) override;
+  bool SendRtp(const uint8_t* packet,
+               size_t length,
+               const PacketOptions& options) override;
   bool SendRtcp(const uint8_t* packet, size_t length) override;
 };
 }  // namespace test