Refactoring: Hide VideoCodec.codecSpecific as "private"

webrtc/modules/video_coding/codecs/vp8/vp8_sequence_coder.cc

Index: webrtc/modules/video_coding/codecs/vp8/vp8_sequence_coder.cc
diff --git a/webrtc/modules/video_coding/codecs/vp8/vp8_sequence_coder.cc b/webrtc/modules/video_coding/codecs/vp8/vp8_sequence_coder.cc
index 006ff65eeed1f9ecd3de351014917166aba01b48..857976d5d266cfc0deb140be97eb63f44fe7f540 100644
--- a/webrtc/modules/video_coding/codecs/vp8/vp8_sequence_coder.cc
+++ b/webrtc/modules/video_coding/codecs/vp8/vp8_sequence_coder.cc
@@ -135,8 +135,8 @@ int SequenceCoder(webrtc::test::CommandLineParser* parser) {
   webrtc::VP8Encoder* encoder = webrtc::VP8Encoder::Create();
   webrtc::VP8Decoder* decoder = webrtc::VP8Decoder::Create();
   inst.codecType = webrtc::kVideoCodecVP8;
-  inst.codecSpecific.VP8.feedbackModeOn = false;
-  inst.codecSpecific.VP8.denoisingOn = true;
+  inst.VP8()->feedbackModeOn = false;
+  inst.VP8()->denoisingOn = true;
   inst.maxFramerate = framerate;
   inst.startBitrate = target_bitrate;
   inst.maxBitrate = 8000;