rustdoc doesn't honor #![doc(html_no_source)] across crates

[QuietMisdreavus]

There's an attribute you can apply to your crate, #![doc(html_no_source)], that tells rustdoc to not generate [src] links or their corresponding files for that crate. However, if a dependency of this crate doesn't add this attribute, and then re-exports something from that crate, it will happily generate [src] links... to nonexistent pages. We should probably track this flag on a per-crate basis for all dependencies, rather than only looking for it in the active crate.

[kadiwa4]

No change; still an issue (nightly 1.69.0 2023-01-22).