Increase the stun ping interval.

webrtc/p2p/base/port.cc

Index: webrtc/p2p/base/port.cc
diff --git a/webrtc/p2p/base/port.cc b/webrtc/p2p/base/port.cc
index fbc64f2e0a784175a2f1f94ae25bac4aca3b710a..0c60da4c699d8ad98b44b858d5db06debd7e9da8 100644
--- a/webrtc/p2p/base/port.cc
+++ b/webrtc/p2p/base/port.cc
@@ -75,6 +75,9 @@ const int RTT_RATIO = 3;  // 3 : 1
 
 // The delay before we begin checking if this port is useless.
 const int kPortTimeoutDelay = 30 * 1000;  // 30 seconds
+
+// First N Pings are sent at a fast rate.
+const int kFirstNPingsWithFastRate = 10;
 }
 
 namespace cricket {
@@ -809,7 +812,8 @@ Connection::Connection(Port* port,
       reported_(false),
       state_(STATE_WAITING),
       receiving_timeout_(WEAK_CONNECTION_RECEIVE_TIMEOUT),
-      time_created_ms_(rtc::TimeMillis()) {
+      time_created_ms_(rtc::TimeMillis()),
+      ping_sent_count_(0) {
   // All of our connections start in WAITING state.
   // TODO(mallinath) - Start connections from STATE_FROZEN.
   // Wire up to send stun packets
@@ -1125,6 +1129,7 @@ void Connection::Ping(int64_t now) {
                           << ", id=" << rtc::hex_encode(req->id());
   requests_.Send(req);
   state_ = STATE_INPROGRESS;
+  ping_sent_count_++;
 }
 
 void Connection::ReceivedPing() {
@@ -1353,6 +1358,10 @@ int64_t Connection::last_received() const {
              std::max(last_ping_received_, last_ping_response_received_));
 }
 
+bool Connection::NeedToPingFast() {
+  return ping_sent_count_ <= kFirstNPingsWithFastRate;
+}
+
 size_t Connection::recv_bytes_second() {
   return round(recv_rate_tracker_.ComputeRate());
 }