Fix SDP stream ID mismatch issue when a track's stream changes.

webrtc/media/base/streamparams.h

 /*
  *  Copyright (c) 2011 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.
  */
 
@@ skipping 234 matching lines @@
 };
 
 template <class Condition>
 const StreamParams* GetStream(const StreamParamsVec& streams,
                               Condition condition) {
   StreamParamsVec::const_iterator found =
       std::find_if(streams.begin(), streams.end(), condition);
   return found == streams.end() ? nullptr : &(*found);
 }
 
+template <class Condition>
+StreamParams* GetStream(StreamParamsVec& streams, Condition condition) {
+  StreamParamsVec::iterator found =
+      std::find_if(streams.begin(), streams.end(), condition);
+  return found == streams.end() ? nullptr : &(*found);
+}
+
 inline const StreamParams* GetStreamBySsrc(const StreamParamsVec& streams,
                                            uint32_t ssrc) {
   return GetStream(streams,
       [&ssrc](const StreamParams& sp) { return sp.has_ssrc(ssrc); });
 }
 
 inline const StreamParams* GetStreamByIds(const StreamParamsVec& streams,
                                           const std::string& groupid,
                                           const std::string& id) {
+  return GetStream(streams, [&groupid, &id](const StreamParams& sp) {
+    return sp.groupid == groupid && sp.id == id;
+  });
+}
+
+inline StreamParams* GetStreamByIds(StreamParamsVec& streams,
+                                    const std::string& groupid,
+                                    const std::string& id) {
   return GetStream(streams,
       [&groupid, &id](const StreamParams& sp) {
         return sp.groupid == groupid && sp.id == id;
       });
 }
 
 inline const StreamParams* GetStream(const StreamParamsVec& streams,
                                      const StreamSelector& selector) {
   return GetStream(streams,
       [&selector](const StreamParams& sp) { return selector.Matches(sp); });
@@ skipping 34 matching lines @@
 bool IsOneSsrcStream(const StreamParams& sp);
 
 // Checks if |sp| defines parameters for one Simulcast stream. There may be RTX
 // streams associated with the simulcast streams. Leaving as non-static so we
 // can test this function.
 bool IsSimulcastStream(const StreamParams& sp);
 
 }  // namespace cricket
 
 #endif  // WEBRTC_MEDIA_BASE_STREAMPARAMS_H_