Rename FecConfig to UlpfecConfig in config.h.

webrtc/config.cc

Index: webrtc/config.cc
diff --git a/webrtc/config.cc b/webrtc/config.cc
index 7c1a0a8bc6ecbdb85198435065b1f3be2d6f2463..0331c0a8332977af9ed035cb73ff1c0cef4a51ca 100644
--- a/webrtc/config.cc
+++ b/webrtc/config.cc
@@ -22,7 +22,7 @@ std::string NackConfig::ToString() const {
   return ss.str();
 }
 
-std::string FecConfig::ToString() const {
+std::string UlpfecConfig::ToString() const {
   std::stringstream ss;
   ss << "{ulpfec_payload_type: " << ulpfec_payload_type;
   ss << ", red_payload_type: " << red_payload_type;