depend_on_referenced_packages triggers falsely on virtual flutter_gen package #58690Description
When a flutter developer adds internationalization to their app as explained in https://docs.flutter.dev/development/accessibility-and-localization/internationalization#adding-your-own-localized-messages it generates a virtual flutter_gen package that the developer has to import in their app (see examples on the linked page). That package does not show up in the pubspec.yaml, but the depend_on_referenced_packages complains about it missing in there.
The flutter_gen package is made available by a rewrite of the package config file. It's a little suspect, but that's what we have right now. Long-term we can hopefully replace this with a macro or something.
In the short-term we need to fix the lint to not complain about this non-existent dependency.