Remove candidates when doing continual gathering

talk/app/webrtc/jsep.h

 /*
  * libjingle
  * Copyright 2012 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 69 matching lines @@
 // This class represents a collection of candidates for a specific m-line.
 // This class is used in SessionDescriptionInterface to represent all known
 // candidates for a certain m-line.
 class IceCandidateCollection {
  public:
   virtual ~IceCandidateCollection() {}
   virtual size_t count() const = 0;
   // Returns true if an equivalent |candidate| exist in the collection.
   virtual bool HasCandidate(const IceCandidateInterface* candidate) const = 0;
   virtual const IceCandidateInterface* at(size_t index) const = 0;
+  // Removes candidates that have a matching address and protocol.
+  // Returns the number of candidates that were removed.
+  virtual int remove(const IceCandidateInterface* candidate) = 0;
 };
 
 // Class representation of a Session description.
 // An instance of this interface is supposed to be owned by one class at
 // a time and is therefore not expected to be thread safe.
 class SessionDescriptionInterface {
  public:
   // Supported types:
   static const char kOffer[];
   static const char kPrAnswer[];
   static const char kAnswer[];
 
   virtual ~SessionDescriptionInterface() {}
   virtual cricket::SessionDescription* description() = 0;
   virtual const cricket::SessionDescription* description() const = 0;
   // Get the session id and session version, which are defined based on
   // RFC 4566 for the SDP o= line.
   virtual std::string session_id() const = 0;
   virtual std::string session_version() const = 0;
   virtual std::string type() const = 0;
   // Adds the specified candidate to the description.
   // Ownership is not transferred.
   // Returns false if the session description does not have a media section that
   // corresponds to the |candidate| label.
   virtual bool AddCandidate(const IceCandidateInterface* candidate) = 0;
+  // Removes the candidate that has a matching 5-tuple from the description.
+  // Returns true if a candidate is found and removed.
+  virtual bool RemoveCandidate(const IceCandidateInterface* candidate) = 0;
   // Returns the number of m- lines in the session description.
   virtual size_t number_of_mediasections() const = 0;
   // Returns a collection of all candidates that belong to a certain m-line
   virtual const IceCandidateCollection* candidates(
       size_t mediasection_index) const = 0;
   // Serializes the description to SDP.
   virtual bool ToString(std::string* out) const = 0;
 };
 
 // Creates a SessionDescriptionInterface based on SDP string and the type.
@@ skipping 21 matching lines @@
   virtual void OnSuccess() = 0;
   virtual void OnFailure(const std::string& error) = 0;
 
  protected:
   ~SetSessionDescriptionObserver() {}
 };
 
 }  // namespace webrtc
 
 #endif  // TALK_APP_WEBRTC_JSEP_H_