Add Common Encryption support to BMFF, including subsample decryption.

media/mp4/avc.h

Index: media/mp4/avc.h
diff --git a/media/mp4/avc.h b/media/mp4/avc.h
index 8e826b01dec39d80c2ffc803924292cebd963487..86eebe07afc0ac7bf0dee2cfe4ddc394ca276cd5 100644
--- a/media/mp4/avc.h
+++ b/media/mp4/avc.h
@@ -17,9 +17,9 @@ struct AVCDecoderConfigurationRecord;
 
 class MEDIA_EXPORT AVC {
  public:
-  static bool ConvertToAnnexB(int length_size, std::vector<uint8>* buffer);
+  static bool ConvertFrameToAnnexB(int length_size, std::vector<uint8>* buffer);
 
-  static bool InsertParameterSets(
+  static bool ConvertParameterSetsToAnnexB(
       const AVCDecoderConfigurationRecord& avc_config,
       std::vector<uint8>* buffer);
 };