Have GetKeyIds() return the key IDs from the first matching 'pssh' box

media/cdm/cenc_utils.h

Index: media/cdm/cenc_utils.h
diff --git a/media/cdm/cenc_utils.h b/media/cdm/cenc_utils.h
index 8938fb92582a6d387db5dae73f99a9e2de4c33c2..f635a325ea63ffa54cd1abc019cc468eee705135 100644
--- a/media/cdm/cenc_utils.h
+++ b/media/cdm/cenc_utils.h
@@ -17,14 +17,18 @@ namespace media {
 // match. Returns true if |input| looks valid, false otherwise.
 MEDIA_EXPORT bool ValidatePsshInput(const std::vector<uint8_t>& input);
 
-// Gets the Key Ids from a 'pssh' box for the Common SystemID among one or
-// more concatenated 'pssh' boxes. If |input| looks valid, then true is
-// returned and |key_ids| is updated to contain the values found. Otherwise
-// return false.
-MEDIA_EXPORT bool GetKeyIdsForCommonSystemId(const std::vector<uint8_t>& input,
-                                             KeyIdList* key_ids);
-
-// Gets the data field from the first 'pssh' box containing |system_id| UUID.
+// Gets the Key Ids from the first 'pssh' box containing |system_id| among one
+// or more concatenated 'pssh' boxes. Returns true if such a box is found and
+// it contains 1 or more key IDs. Returns false otherwise.
+// Notes:
+// 1. If multiple PSSH boxes are found, the "KIDs" of the first matching 'pssh'
+//    box will be set in |key_ids|.
+// 2. Only PSSH boxes are allowed in |input|.
+MEDIA_EXPORT bool GetKeyIds(const std::vector<uint8_t>& input,
+                            const std::vector<uint8_t>& system_id,
+                            KeyIdList* key_ids);
+
+// Gets the data field from the first 'pssh' box containing |system_id|.
 // Returns true if such a box is found and successfully parsed. Returns false
 // otherwise.
 // Notes: