Reland the CL to remove candidates when doing continual gathering

webrtc/api/jsep.h

 /*
  *  Copyright 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 // Interfaces matching the draft-ietf-rtcweb-jsep-01.
 
 #ifndef WEBRTC_API_JSEP_H_
 #define WEBRTC_API_JSEP_H_
 
 #include <string>
 #include <vector>
 
 #include "webrtc/base/basictypes.h"
 #include "webrtc/base/refcount.h"
 
 namespace cricket {
+class Candidate;
 class SessionDescription;
-class Candidate;
 }  // namespace cricket
 
 namespace webrtc {
 
 struct SdpParseError {
  public:
   // The sdp line that causes the error.
   std::string line;
   // Explains the error.
   std::string description;
@@ skipping 53 matching lines @@
   // 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 candidates from the description.
+  // Returns the number of candidates removed.
+  virtual size_t RemoveCandidates(
+      const std::vector<cricket::Candidate>& candidates) { return 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  // WEBRTC_API_JSEP_H_