Remove candidates when doing continual gathering

talk/app/webrtc/webrtcsession.h

Index: talk/app/webrtc/webrtcsession.h
diff --git a/talk/app/webrtc/webrtcsession.h b/talk/app/webrtc/webrtcsession.h
index cd3f8967261232faee479eb26d370907b23566e9..1c5f432fa9d4f6701c52ac7ea9f51c675a1794e4 100644
--- a/talk/app/webrtc/webrtcsession.h
+++ b/talk/app/webrtc/webrtcsession.h
@@ -401,6 +401,10 @@ class WebRtcSession : public AudioProviderInterface,
       const SessionDescriptionInterface* remote_desc);
   // Uses |candidate| in this session.
   bool UseCandidate(const IceCandidateInterface* candidate);
+  // Stops using a remote candidate in this session.
+  bool StopUsingCandidate(const IceCandidateInterface* candidate);

[pthatcher1, 2016/02/10 00:01:41]

Can use change UseCandidate to be AddCandidate, and then call this
RemoveCandidate?

[honghaiz3, 2016/02/10 19:22:44]

Done.Using AddRemoteCandidate RemoveRemoteCandidate. 

+  const cricket::ContentInfo* GetRemoteMediaContent(
+      const IceCandidateInterface* candidate) const;
   // Deletes the corresponding channel of contents that don't exist in |desc|.
   // |desc| can be null. This means that all channels are deleted.
   void RemoveUnusedChannels(const cricket::SessionDescription* desc);
@@ -454,6 +458,9 @@ class WebRtcSession : public AudioProviderInterface,
   void OnTransportControllerCandidatesGathered(
       const std::string& transport_name,
       const cricket::Candidates& candidates);
+  void OnTransportControllerCandidatesRemoved(
+      const std::string& transport_name,
+      const cricket::Candidates& candidates);
 
   std::string GetSessionErrorMsg();