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

media/cdm/aes_decryptor.cc

Index: media/cdm/aes_decryptor.cc
diff --git a/media/cdm/aes_decryptor.cc b/media/cdm/aes_decryptor.cc
index c145b008c5d0b2167572172f0057091ebafa239a..64e31d4da4415d3c0489c31047769bfbcacef213 100644
--- a/media/cdm/aes_decryptor.cc
+++ b/media/cdm/aes_decryptor.cc
@@ -27,6 +27,12 @@
 
 namespace media {
 
+// SystemID for the Common System.
+// https://w3c.github.io/encrypted-media/cenc-format.html#common-system
+const uint8_t kCommonSystemId[] = {0x10, 0x77, 0xef, 0xec, 0xc0, 0xb2,
+                                   0x4d, 0x02, 0xac, 0xe3, 0x3c, 0x1e,
+                                   0x52, 0xe2, 0xfb, 0x4b};
+
 // Keeps track of the session IDs and DecryptionKeys. The keys are ordered by
 // insertion time (last insertion is first). It takes ownership of the
 // DecryptionKeys.
@@ -275,13 +281,16 @@ void AesDecryptor::CreateSessionAndGenerateRequest(
         break;
       case EmeInitDataType::CENC:
 #if defined(USE_PROPRIETARY_CODECS)
+      {
         // |init_data| is a set of 0 or more concatenated 'pssh' boxes.
-        if (!GetKeyIdsForCommonSystemId(init_data, &keys)) {
+        std::vector<uint8_t> common_system_id(
+            kCommonSystemId, kCommonSystemId + arraysize(kCommonSystemId));
+        if (!GetKeyIds(init_data, common_system_id, &keys)) {
           promise->reject(NOT_SUPPORTED_ERROR, 0,
                           "No supported PSSH box found.");
           return;
         }
-        break;
+      } break;
 #else
         promise->reject(NOT_SUPPORTED_ERROR, 0,
                         "Initialization data type CENC is not supported.");