fast-rustc-ap-rustc_errors is used at run time in 3 crates.

Depender (with downloads and own rev deps) fast-rustc-ap-rustc_errors version
1 fast-rustc-ap-rustc_attr ^1.0.0
fast-rustc-ap-rustc_parse ^1.0.0
2 fast-rustc-ap-rustc_session ^1.0.0