Delete class NullRtpData and function NullObjectRtpData

webrtc/modules/rtp_rtcp/test/testAPI/test_api.cc

Index: webrtc/modules/rtp_rtcp/test/testAPI/test_api.cc
diff --git a/webrtc/modules/rtp_rtcp/test/testAPI/test_api.cc b/webrtc/modules/rtp_rtcp/test/testAPI/test_api.cc
index 4eac882bb0a66591e8f5b47c04a223715e643b9c..a77f11403f40a714c0156c4b055ec7ed15424015 100644
--- a/webrtc/modules/rtp_rtcp/test/testAPI/test_api.cc
+++ b/webrtc/modules/rtp_rtcp/test/testAPI/test_api.cc
@@ -106,10 +106,11 @@ class RtpRtcpAPITest : public ::testing::Test {
     module_->SetSSRC(initial_ssrc);
     rtp_payload_registry_.reset(new RTPPayloadRegistry());
     rtp_receiver_.reset(RtpReceiver::CreateAudioReceiver(
-        &fake_clock_, NULL, NULL, rtp_payload_registry_.get()));
+        &fake_clock_, &null_rtp_data_, NULL, rtp_payload_registry_.get()));
   }
 
   std::unique_ptr<RTPPayloadRegistry> rtp_payload_registry_;
+  NullRtpData null_rtp_data_;
   std::unique_ptr<RtpReceiver> rtp_receiver_;
   std::unique_ptr<RtpRtcp> module_;
   uint32_t test_ssrc_;