Calling LibraryResult.toBundle() could have caused a CastClassException.
This was because when unbundled with UNKNOWN_TYPE_CREATOR.fromBundle(Bundle),
the valueType was set to VALUE_TYPE_ITEM_LIST for all types and the MediaItem
was attempted to be casted to a list.
PiperOrigin-RevId: 529717688
(cherry picked from commit f28a5888091c5caa685117d7a6653ae6c5a29f26)