Delete class NullRtpData and function NullObjectRtpData

webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl_unittest.cc

Index: webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl_unittest.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl_unittest.cc b/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl_unittest.cc
index 75e2dc17d1e51be6f6fb715905003b4a6a886beb..783fe5eaddfca5598a19472e0f281c8ab4246655 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl_unittest.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl_unittest.cc
@@ -50,7 +50,7 @@ class RtcpRttStatsTestImpl : public RtcpRttStats {
 };
 
 class SendTransport : public Transport,
-                      public NullRtpData {
+                      public RtpData {
  public:
   SendTransport()
       : receiver_(NULL),
@@ -88,6 +88,11 @@ class SendTransport : public Transport,
     EXPECT_EQ(0, receiver_->IncomingRtcpPacket(data, len));
     return true;
   }
+  int32_t OnReceivedPayloadData(const uint8_t* payload_data,
+                                size_t payload_size,
+                                const WebRtcRTPHeader* rtp_header) override {
+    return 0;
+  }
   ModuleRtpRtcpImpl* receiver_;
   SimulatedClock* clock_;
   int64_t delay_ms_;