Bitrate prober and paced sender improvements

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 e8967abde45977753ff096acdc9016ba2b3b1e2f..c2f9ad8c4713db52ea8d000b6ca1d554d31d5adf 100644
--- a/webrtc/modules/pacing/bitrate_prober.h
+++ b/webrtc/modules/pacing/bitrate_prober.h
@@ -55,7 +55,18 @@ class BitrateProber {
   void PacketSent(int64_t now_ms, size_t packet_size);
 
  private:
-  enum ProbingState { kDisabled, kAllowedToProbe, kProbing, kWait };
+  enum class ProbingState {
+    // Probing will not be triggered in this state at all times.
+    kDisabled,
+    // Probing is enabled and ready to trigger on the first packet arrival.
+    kInactive,
+    // Probe cluster is filled with the set of data rates to be probed and
+    // probes are being sent.
+    kActive,
+    // Probing is enabled, but currently suspended until an explicit trigger
+    // to start probing again.
+    kSuspended,
+  };
 
   struct ProbeCluster {
     int max_probe_packets = 0;
@@ -64,13 +75,17 @@ class BitrateProber {
     int id = -1;
   };
 
+  // Resets the state of the prober and clears any cluster/timing data tracked.
+  void ResetState();
+
   ProbingState probing_state_;
   // Probe bitrate per packet. These are used to compute the delta relative to
   // the previous probe packet based on the size and time when that packet was
   // sent.
   std::queue<ProbeCluster> clusters_;
-  size_t packet_size_last_send_;
-  int64_t time_last_send_ms_;
+  size_t packet_size_last_sent_;
+  // The last time a probe was sent.
+  int64_t time_last_probe_sent_ms_;
   int next_cluster_id_;
 };
 }  // namespace webrtc