Add ability to cap the video jitter estimate to a max value.

Bug: webrtc:10572
Change-Id: I21112824dc02afa71db61bb8c2f02723e8b325b6
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/133963
Commit-Queue: Michael Horowitz <mhoro@webrtc.org>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27744}

modules/video_coding/jitter_estimator.h

@@ -47,7 +47,7 @@ class VCMJitterEstimator {
   //          - rttMultiplier  : RTT param multiplier (when applicable).
   //
   // Return value              : Jitter estimate in milliseconds.
-  virtual int GetJitterEstimate(double rttMultiplier);
+  virtual int GetJitterEstimate(double rttMultiplier, double jitterEstCapMs);
 
   // Updates the nack counter.
   void FrameNacked();