Fix capture ntp time issue introduced with r11187.

webrtc/call/call_perf_tests.cc

Index: webrtc/call/call_perf_tests.cc
diff --git a/webrtc/call/call_perf_tests.cc b/webrtc/call/call_perf_tests.cc
index 86cd9ae072f2c8e9f5b7fb22af81137d19e5c0db..3adcb10b09123826ac6fb73e18f673a969a77b6e 100644
--- a/webrtc/call/call_perf_tests.cc
+++ b/webrtc/call/call_perf_tests.cc
@@ -405,6 +405,11 @@ void CallPerfTest::TestCaptureNtpTime(const FakeNetworkPipe::Config& net_config,
           sender_call, this, test::PacketTransport::kSender, net_config_);
     }
 
+    test::PacketTransport* CreateReceiveTransport() override {
+      return new test::PacketTransport(
+          nullptr, this, test::PacketTransport::kReceiver, net_config_);
+    }
+
     void RenderFrame(const VideoFrame& video_frame,
                      int time_to_render_ms) override {
       rtc::CritScope lock(&crit_);