fix: Fix legacy codec support by rewriting codec metadata (#4858)

This fixes legacy codec support by rewriting the codec metadata in the
Stream objects. After capability checking, the converted codec
information will be used.

Co-authored-by: Joey Parrish <[email protected]>

lib/util/stream_utils.js

@@ -459,12 +459,16 @@ shaka.util.StreamUtils = class {
           if (!Capabilities.isTypeSupported(audioFullType)) {
             return false;
           }
+          // Update the codec string with the (possibly) converted codecs.
+          videoCodecs = [videoCodecs, audioCodecs].join(',');
         }
         const fullType = shaka.util.MimeUtils.getFullOrConvertedType(
             video.mimeType, videoCodecs, ContentType.VIDEO);
         if (!Capabilities.isTypeSupported(fullType)) {
           return false;
         }
+        // Update the codec string with the (possibly) converted codecs.
+        video.codecs = videoCodecs;
       }
       const audio = variant.audio;
       if (audio) {
@@ -475,6 +479,8 @@ shaka.util.StreamUtils = class {
         if (!Capabilities.isTypeSupported(fullType)) {
           return false;
         }
+        // Update the codec string with the (possibly) converted codecs.
+        audio.codecs = codecs;
       }
 
       // See: https://github.com/shaka-project/shaka-player/issues/3380