More gracefully handle rtp timestamp jumps in the rtp to ntp estimator.

webrtc/system_wrappers/include/rtp_to_ntp_estimator.h

Index: webrtc/system_wrappers/include/rtp_to_ntp_estimator.h
diff --git a/webrtc/system_wrappers/include/rtp_to_ntp_estimator.h b/webrtc/system_wrappers/include/rtp_to_ntp_estimator.h
index a17428bf2730c4a0a68d06aaf1d69c418cc8dfd8..9d6da051d5027bd8f3a8a0d2a71818d0ac226547 100644
--- a/webrtc/system_wrappers/include/rtp_to_ntp_estimator.h
+++ b/webrtc/system_wrappers/include/rtp_to_ntp_estimator.h
@@ -54,9 +54,12 @@ class RtpToNtpEstimator {
 
   const Parameters& params() const { return params_; }
 
+  static const int kMaxInvalidSamples = 3;
+
  private:
   void UpdateParameters();
 
+  int consecutive_invalid_samples_;
   std::list<RtcpMeasurement> measurements_;
   Parameters params_;
 };