[in_app_purchase] Unused json_annotation-generated code #183937

Pub.dev is giving this package a score deduction due to unused generated code:

WARNING: The declaration '_$SerializedEnumsFromJson' isn't referenced.
lib/src/store_kit_wrappers/enum_converters.g.dart:9:18

  ╷
9 │ _SerializedEnums _$SerializedEnumsFromJson(Map json) => _SerializedEnums()
  │                  ^^^^^^^^^^^^^^^^^^^^^^^^^
  ╵

WARNING: The declaration '_$SKPaymentDiscountWrapperToJson' isn't referenced.
lib/src/store_kit_wrappers/sk_payment_queue_wrapper.g.dart:49:22

   ╷
49 │ Map<String, dynamic> _$SKPaymentDiscountWrapperToJson(
   │                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

We don't catch this locally because we mostly exempt generated code from the analyzer in our repo settings; pub.dev uses standardized analysis options rather than ours.

I haven't investigated to see if this is a bug in the generation itself, or if we are generating code that we no longer need to. It may very well be the latter since we used to use JSON for platform channel communication, and now use Pigeon instead.

This doesn't actually matter for production, due to tree shaking; investigating this would be purely for pub.dev score.