Some cleanup in BaseChannel RTCP mux code.

webrtc/pc/rtcpmuxfilter.h

 /*
  *  Copyright 2004 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.
  */
 
 #ifndef WEBRTC_PC_RTCPMUXFILTER_H_
 #define WEBRTC_PC_RTCPMUXFILTER_H_
 
 #include "webrtc/base/basictypes.h"
 #include "webrtc/p2p/base/sessiondescription.h"
 
 namespace cricket {
 
 // RTCP Muxer, as defined in RFC 5761 (http://tools.ietf.org/html/rfc5761)
 class RtcpMuxFilter {
  public:
   RtcpMuxFilter();
 
-  // Whether the filter is active, i.e. has RTCP mux been properly negotiated.
+  // Whether RTCP mux has been negotiated with a final answer (not provisional).
+  bool IsFullyActive() const;
+
+  // Whether RTCP mux has been negotiated with a provisional answer; this means
+  // a later answer could disable RTCP mux, and so the RTCP transport should
+  // not be disposed yet.
+  bool IsProvisionallyActive() const;
+
+  // Whether the filter is active, i.e. has RTCP mux been properly negotiated,
+  // either with a final or provisional answer.
   bool IsActive() const;
 
-  // Make the filter active, regardless of the current state.
+  // Make the filter active (fully, not provisionally) regardless of the
+  // current state. This should be used when an endpoint *requires* RTCP mux.
   void SetActive();
 
   // Specifies whether the offer indicates the use of RTCP mux.
   bool SetOffer(bool offer_enable, ContentSource src);
 
   // Specifies whether the provisional answer indicates the use of RTCP mux.
   bool SetProvisionalAnswer(bool answer_enable, ContentSource src);
 
   // Specifies whether the answer indicates the use of RTCP mux.
   bool SetAnswer(bool answer_enable, ContentSource src);
@@ skipping 25 matching lines @@
     // the filter.
     ST_ACTIVE
   };
   State state_;
   bool offer_enable_;
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_PC_RTCPMUXFILTER_H_