Add VP8 codec enum to video decoder.

media/filters/ffmpeg_video_decoder.cc

Index: media/filters/ffmpeg_video_decoder.cc
diff --git a/media/filters/ffmpeg_video_decoder.cc b/media/filters/ffmpeg_video_decoder.cc
index 7d73cc812e2358929e21c40b1a36decc8fdaef97..15453ffb2253722c3286853f72ef4e053dfdb097 100644
--- a/media/filters/ffmpeg_video_decoder.cc
+++ b/media/filters/ffmpeg_video_decoder.cc
@@ -89,6 +89,8 @@ void FFmpegVideoDecoder::Initialize(DemuxerStream* demuxer_stream,
       config.codec_ = kCodecMPEG2; break;
     case CODEC_ID_MPEG4:
       config.codec_ = kCodecMPEG4; break;
+    case CODEC_ID_VP8:
+      config.codec_ = kCodecVP8; break;
     default:
       NOTREACHED();
   }