Dampening connection switch.

webrtc/p2p/base/port.h

Index: webrtc/p2p/base/port.h
diff --git a/webrtc/p2p/base/port.h b/webrtc/p2p/base/port.h
index 2c3b61b718307173d152a1c8f35ecf933b00aaed..37926c955603a3f27918270b5b43b177cdccddf9 100644
--- a/webrtc/p2p/base/port.h
+++ b/webrtc/p2p/base/port.h
@@ -590,6 +590,10 @@ class Connection : public CandidatePairInterface,
   // Returns the last received time of any data, stun request, or stun
   // response in milliseconds
   int64_t last_received() const;
+  // Returns the last time when the connection changed its receiving state.
+  int64_t receiving_unchanged_since() const {
+    return receiving_unchanged_since_;
+  }
 
   bool stable(int64_t now) const;
 
@@ -618,7 +622,7 @@ class Connection : public CandidatePairInterface,
 
   // Changes the state and signals if necessary.
   void set_write_state(WriteState value);
-  void set_receiving(bool value);
+  void UpdateReceiving(int64_t now);
   void set_state(State state);
   void set_connected(bool value);
 
@@ -648,6 +652,7 @@ class Connection : public CandidatePairInterface,
                                 // side
   int64_t last_data_received_;
   int64_t last_ping_response_received_;
+  int64_t receiving_unchanged_since_ = 0;
   std::vector<SentPing> pings_since_last_response_;
 
   rtc::RateTracker recv_rate_tracker_;