rustc-ap-rustc_error_codes 638.0.0

Automatically published version of the package `rustc_error_codes` in the rust-lang/rust repository from commit 30ca215b4e38b32aa7abdd635c5e2d56f5724494 The publishing script for this crate lives at: https://github.com/alexcrichton/rustc-auto-publish
Documentation
This library is used to gather all error codes into one place, the goal being to make their maintenance easier.