MP4 support for Common Encryption 'cbcs' scheme.

media/formats/mp4/track_run_iterator.h

Index: media/formats/mp4/track_run_iterator.h
diff --git a/media/formats/mp4/track_run_iterator.h b/media/formats/mp4/track_run_iterator.h
index a04f2becb5c0f44b6d35f37524a3cbd49e7d6deb..127cafa8a6671fcb971282b4f4cfa87894a227d1 100644
--- a/media/formats/mp4/track_run_iterator.h
+++ b/media/formats/mp4/track_run_iterator.h
@@ -17,6 +17,7 @@
 #include "media/base/media_log.h"
 #include "media/base/stream_parser_buffer.h"
 #include "media/formats/mp4/box_definitions.h"
+#include "media/media_features.h"
 
 namespace media {
 
@@ -99,6 +100,9 @@ class MEDIA_EXPORT TrackRunIterator {
   bool IsSampleEncrypted(size_t sample_index) const;
   uint8_t GetIvSize(size_t sample_index) const;
   const std::vector<uint8_t>& GetKeyId(size_t sample_index) const;
+#if BUILDFLAG(ENABLE_CBCS_ENCRYPTION_SCHEME)
+  bool ApplyConstantIv(size_t sample_index, SampleEncryptionEntry* entry) const;
+#endif
 
   const Movie* moov_;
   scoped_refptr<MediaLog> media_log_;