When importing path_parsing, I had to add // ignores for library_private_types_in_public_api, because refactoring code visibility was out of scope for the import. We should fix that and remove the // ignore so that we are following the best practices that our analysis_options are intended to enforce.

I suspect that the right fix is to make the things using private types private; technically that would be a breaking change, but since there shouldn't be any way for clients to be using them we might be able to do it as a non-breaking change. We'd want to check the public packages using it to ensure at least none of them are somehow referencing those symbols.

Alternately we could make the types public. I didn't evaluate how much that adds to our permanent API surface.