Update Cdm Wrapper and ClearKeyCdm to work with CDM interface version 4.

webkit/media/crypto/ppapi/ffmpeg_cdm_audio_decoder.h

Index: webkit/media/crypto/ppapi/ffmpeg_cdm_audio_decoder.h
diff --git a/webkit/media/crypto/ppapi/ffmpeg_cdm_audio_decoder.h b/webkit/media/crypto/ppapi/ffmpeg_cdm_audio_decoder.h
index 994f0be16c87182f0c1d8a03475d94ed9b8133b5..d9ca867065d0473afd6a275a7b51841b9a9acdeb 100644
--- a/webkit/media/crypto/ppapi/ffmpeg_cdm_audio_decoder.h
+++ b/webkit/media/crypto/ppapi/ffmpeg_cdm_audio_decoder.h
@@ -29,7 +29,7 @@ namespace webkit_media {
 // solution for this. See http://crbug.com/169203
 class FFmpegCdmAudioDecoder {
  public:
-  explicit FFmpegCdmAudioDecoder(cdm::Allocator* allocator);
+  explicit FFmpegCdmAudioDecoder(cdm::Host* host);
   ~FFmpegCdmAudioDecoder();
   bool Initialize(const cdm::AudioDecoderConfig& config);
   void Deinitialize();
@@ -57,7 +57,7 @@ class FFmpegCdmAudioDecoder {
 
   bool is_initialized_;
 
-  cdm::Allocator* const allocator_;
+  cdm::Host* const host_;
 
   // FFmpeg structures owned by this object.
   AVCodecContext* codec_context_;