Fixing issue where description contains empty ICE ufrag/pwd.

talk/app/webrtc/webrtcsdp.cc

 /*
  * libjingle
  * Copyright 2011 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 1277 matching lines @@
   // Build the a=candidate lines. We don't include ufrag and pwd in the
   // candidates in the SDP to avoid redundancy.
   BuildCandidate(candidates, false, message);
 
   // Use the transport_info to build the media level ice-ufrag and ice-pwd.
   if (transport_info) {
     // RFC 5245
     // ice-pwd-att           = "ice-pwd" ":" password
     // ice-ufrag-att         = "ice-ufrag" ":" ufrag
     // ice-ufrag
-    InitAttrLine(kAttributeIceUfrag, &os);
-    os << kSdpDelimiterColon << transport_info->description.ice_ufrag;
-    AddLine(os.str(), message);
+    if (!transport_info->description.ice_ufrag.empty()) {
+      InitAttrLine(kAttributeIceUfrag, &os);
+      os << kSdpDelimiterColon << transport_info->description.ice_ufrag;
+      AddLine(os.str(), message);
+    }
     // ice-pwd
-    InitAttrLine(kAttributeIcePwd, &os);
-    os << kSdpDelimiterColon << transport_info->description.ice_pwd;
-    AddLine(os.str(), message);
+    if (!transport_info->description.ice_pwd.empty()) {
+      InitAttrLine(kAttributeIcePwd, &os);
+      os << kSdpDelimiterColon << transport_info->description.ice_pwd;
+      AddLine(os.str(), message);
+    }
 
     // draft-petithuguenin-mmusic-ice-attributes-level-03
     BuildIceOptions(transport_info->description.transport_options, message);
 
     // RFC 4572
     // fingerprint-attribute  =
     //   "fingerprint" ":" hash-func SP fingerprint
     if (fp) {
       // Insert the fingerprint attribute.
       InitAttrLine(kAttributeFingerprint, &os);
@@ skipping 1758 matching lines @@
     UpdateCodec<AudioContentDescription, cricket::AudioCodec>(
         media_desc, payload_type, feedback_param);
   } else if (media_type == cricket::MEDIA_TYPE_VIDEO) {
     UpdateCodec<VideoContentDescription, cricket::VideoCodec>(
         media_desc, payload_type, feedback_param);
   }
   return true;
 }
 
 }  // namespace webrtc