Add new codec for FlexFEC.

webrtc/media/engine/payload_type_mapper.cc

Index: webrtc/media/engine/payload_type_mapper.cc
diff --git a/webrtc/media/engine/payload_type_mapper.cc b/webrtc/media/engine/payload_type_mapper.cc
index 87b54be33b51f530e0aac15da859d614bba7eedd..58eab16eada9de773d250d44ce5a51f54ea2c490 100644
--- a/webrtc/media/engine/payload_type_mapper.cc
+++ b/webrtc/media/engine/payload_type_mapper.cc
@@ -84,6 +84,7 @@ PayloadTypeMapper::PayloadTypeMapper()
               {{"minptime", "10"}, {"useinbandfec", "1"}}}, 111},
           {{kRedCodecName,    90000, 0}, kDefaultRedPlType},
           {{kUlpfecCodecName, 90000, 0}, kDefaultUlpfecType},
+          {{kFlexfecCodecName, 90000, 0}, kDefaultFlexfecPlType},
           {{kDtmfCodecName,    8000, 1}, 126}}) {
   // TODO(ossu): Try to keep this as change-proof as possible until we're able
   // to remove the payload type constants from everywhere in the code.