Adding FEC support in NetEq 4.

R=henrik.lundin@webrtc.org, turaj@webrtc.org

TEST=passes all trybots

BUG=

Review URL: https://webrtc-codereview.appspot.com/9999004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5748 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/modules/audio_coding/neteq4/timestamp_scaler.cc

@@ -55,7 +55,8 @@ uint32_t TimestampScaler::ToInternal(uint32_t external_timestamp,
       // Use timestamp scaling with factor 2/3 (32 kHz sample rate, but RTP
       // timestamps run on 48 kHz).
       // TODO(tlegrand): Remove scaling for kDecoderCNGswb48kHz once ACM has
-      // full 48 kHz support.
+      // full 48 kHz support. Change also ought to be made in
+      // PayloadSplitter::SplitFec().
       numerator_ = 2;
       denominator_ = 3;
     }