Hotfix for psnr regresion with fec tests caused by timing frames.

webrtc/modules/rtp_rtcp/source/rtp_sender_unittest.cc

Index: webrtc/modules/rtp_rtcp/source/rtp_sender_unittest.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_sender_unittest.cc b/webrtc/modules/rtp_rtcp/source/rtp_sender_unittest.cc
index 3c5c116cb053655cc03d61758d29462d13b745fb..3e9ed6e195416c930f4652327ef57b5ed83b5248 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_sender_unittest.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtp_sender_unittest.cc
@@ -463,7 +463,9 @@ TEST_P(RtpSenderTest, SendsPacketsWithTransportSequenceNumber) {
   EXPECT_EQ(transport_.last_packet_id_, transport_seq_no);
 }
 
-TEST_P(RtpSenderTestWithoutPacer, WritesTimestampToTimingExtension) {
+// Disabled due to webrtc:7859. Until issues with FEC resolved, pacer exit
+// timstamp is not updated in the pacer.
+TEST_P(RtpSenderTestWithoutPacer, DISABLED_WritesTimestampToTimingExtension) {
   rtp_sender_->SetStorePacketsStatus(true, 10);
   EXPECT_EQ(0, rtp_sender_->RegisterRtpHeaderExtension(
                    kRtpExtensionVideoTiming, kVideoTimingExtensionId));