Propagate packet pacing information to SenTimeHistory

webrtc/modules/pacing/bitrate_prober.h

Index: webrtc/modules/pacing/bitrate_prober.h
diff --git a/webrtc/modules/pacing/bitrate_prober.h b/webrtc/modules/pacing/bitrate_prober.h
index 225ee9e157bed7d3cfe16861ebbe3c59de93e198..0c27e42e6ef0ea8672eeaa5469c93ec0b5e54278 100644
--- a/webrtc/modules/pacing/bitrate_prober.h
+++ b/webrtc/modules/pacing/bitrate_prober.h
@@ -18,12 +18,22 @@
 
 namespace webrtc {
 
+class ProbeClusterCreatedObserver {
+ public:
+  virtual ~ProbeClusterCreatedObserver() {}
+  virtual void OnProbingClusterCreated(int cluster_id,

[nisse-webrtc, 2017/01/10 16:04:41]

Please document what the parameters mean.

Might also make sense to collect them into a struct and pass a const&.

It's unclear to me what use the CongestionController can make of the fact that a
probe was created. I would have expected the measurement *results*, once the
probe is complete and ACKs are seen, to be signalled to the
CongestionController.

[philipel, 2017/01/11 09:03:33]

Done
The CongestionController can't do anything with this data other than pass it on.
The reason the CongestionController is the class that implements this interface
is because it is the first class that connects the BitrateProber and the
ProbeBitrateEstimator.

[nisse-webrtc, 2017/01/11 09:10:32]

Even if it delegates the processing, I still don't see how it's useful. The
result of the probe is needed before it can be useful for estimating stuff.

Or is this rather a *request* to start sending a new probe? If so, I think it
needs a different name. 

I feel I don't grasp the big picture here.

+                                       int min_bytes,
+                                       int min_probes) = 0;
+};
+
 // Note that this class isn't thread-safe by itself and therefore relies
 // on being protected by the caller.
 class BitrateProber {
  public:
   BitrateProber();
 
+  explicit BitrateProber(ProbeClusterCreatedObserver* cluster_created_observer);
+
   void SetEnabled(bool enable);
 
   // Returns true if the prober is in a probing session, i.e., it currently
@@ -100,6 +110,8 @@ class BitrateProber {
   int64_t next_probe_time_ms_;
 
   int next_cluster_id_;
+
+  ProbeClusterCreatedObserver* cluster_created_observer_;
 };
 
 }  // namespace webrtc