First step of passive aggressive nomination.

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 4023b322e732ef31e6827bd3fc95715351fc2f22..d5ea551e676689570299c972239421de8455f1ee 100644
--- a/webrtc/p2p/base/port.cc
+++ b/webrtc/p2p/base/port.cc
@@ -887,6 +887,7 @@ Connection::Connection(Port* port,
       connected_(true),
       pruned_(false),
       use_candidate_attr_(false),
+      nominated_(false),
       remote_ice_mode_(ICEMODE_FULL),
       requests_(port->thread()),
       rtt_(DEFAULT_RTT),
@@ -1057,7 +1058,7 @@ void Connection::OnReadPacket(
             const StunByteStringAttribute* use_candidate_attr =
                 msg->GetByteString(STUN_ATTR_USE_CANDIDATE);
             if (use_candidate_attr)
-              SignalUseCandidate(this);
+              set_nominated(true);
           }
         } else {
           // The packet had the right local username, but the remote username
@@ -1473,6 +1474,13 @@ size_t Connection::sent_total_packets() {
   return sent_packets_total_;
 }
 
+void Connection::set_nominated(bool nominated) {
+  nominated_ = nominated;
+  if (nominated_) {
+    SignalUseCandidate(this);

[juberti1, 2015/08/07 01:31:19]

This seems like an unexpected side effect. I would suggest that the code that
calls set_nominated just invoke the relevant OnUseCandidate logic directly.

[honghaiz3, 2015/08/07 20:42:04]

Done.

+  }
+}
+
 void Connection::MaybeAddPrflxCandidate(ConnectionRequest* request,
                                         StunMessage* response) {
   // RFC 5245