Add FFmpeg audio decoder for the clear key CDM.

webkit/media/crypto/ppapi/ffmpeg_cdm_video_decoder.cc

Index: webkit/media/crypto/ppapi/ffmpeg_cdm_video_decoder.cc
diff --git a/webkit/media/crypto/ppapi/ffmpeg_cdm_video_decoder.cc b/webkit/media/crypto/ppapi/ffmpeg_cdm_video_decoder.cc
index ebf482de359229cbf550c0c0bd0cf26aac5ee6d3..b26823584e4a03e1389078ad011674be307deb36 100644
--- a/webkit/media/crypto/ppapi/ffmpeg_cdm_video_decoder.cc
+++ b/webkit/media/crypto/ppapi/ffmpeg_cdm_video_decoder.cc
@@ -8,7 +8,6 @@
 #include "base/memory/scoped_ptr.h"
 #include "media/base/buffers.h"
 #include "media/base/limits.h"
-#include "media/ffmpeg/ffmpeg_common.h"
 #include "webkit/media/crypto/ppapi/content_decryption_module.h"
 
 // Include FFmpeg header files.
@@ -125,8 +124,6 @@ bool FFmpegCdmVideoDecoder::Initialize(const cdm::VideoDecoderConfig& config) {
     return false;
   }
 
-  av_register_all();
-
   // Release existing resources if necessary.
   ReleaseFFmpegResources();