Support parsing of sgpd and sbgp boxes

media/formats/mp4/box_definitions.h

Index: media/formats/mp4/box_definitions.h
diff --git a/media/formats/mp4/box_definitions.h b/media/formats/mp4/box_definitions.h
index 5aa0e493a6c94c700d037a4940661969d7467a31..c7129b0a3a8977981b08d0dc5cec261c812d000c 100644
--- a/media/formats/mp4/box_definitions.h
+++ b/media/formats/mp4/box_definitions.h
@@ -365,6 +365,40 @@ class MEDIA_EXPORT IndependentAndDisposableSamples : public Box {
   std::vector<SampleDependsOn> sample_depends_on_;
 };
 
+struct MEDIA_EXPORT CencSampleEncryptionInfoEntry {
+  CencSampleEncryptionInfoEntry();
+  ~CencSampleEncryptionInfoEntry();
+
+  bool is_encrypted;
+  uint8 iv_size;
+  std::vector<uint8> key_id;
+};
+
+struct MEDIA_EXPORT SampleGroupDescription : Box {  // 'sgpd'.
+  DECLARE_BOX_METHODS(SampleGroupDescription);
+
+  uint32 grouping_type;
+  std::vector<CencSampleEncryptionInfoEntry> entries;
+};
+
+struct MEDIA_EXPORT SampleToGroupEntry {
+  enum GroupDescriptionIndexBase {
+    kTrackGroupDescriptionIndexBase = 0,
+    kFragmentGroupDescriptionIndexBase = 0x10000,
+  };
+
+  uint32 sample_count;
+  uint32 group_description_index;
+};
+
+struct MEDIA_EXPORT SampleToGroup : Box {  // 'sbgp'.
+  DECLARE_BOX_METHODS(SampleToGroup);
+
+  uint32 grouping_type;
+  uint32 grouping_type_parameter;  // Version 1 only.
+  std::vector<SampleToGroupEntry> entries;
+};
+
 struct MEDIA_EXPORT TrackFragment : Box {
   DECLARE_BOX_METHODS(TrackFragment);
 
@@ -374,6 +408,8 @@ struct MEDIA_EXPORT TrackFragment : Box {
   SampleAuxiliaryInformationOffset auxiliary_offset;
   SampleAuxiliaryInformationSize auxiliary_size;
   IndependentAndDisposableSamples sdtp;
+  SampleGroupDescription sample_group_description;
+  SampleToGroup sample_to_group;
 };
 
 struct MEDIA_EXPORT MovieFragment : Box {