Query docs show return types as `<query_name as QueryConfig<TyCtxt<'tcx>>>::Stored`

[jyn514]

e.g. https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.TyCtxt.html#method.hir_crate

This makes the docs really hard to read: you have to click on hir_crate, open impl<'tcx> QueryConfig<TyCtxt<'tcx>> for hir_crate, and know that Value is what actually matters, not Stored. This is super confusing and not documented anywhere. We should find a way to just put &'tcx Crate<'tcx> directly in the return type instead.

[jyn514]

TyCtxtAt has the same problem: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/query/struct.TyCtxtAt.html#method.hir_crate

[jyn514]

I'm not sure what's going on with Stored here:
eval_to_const_value_raw returns EvalToConstValueResult (not a borrow), while
generics_of returns &ty::Generics (a borrow). However in the query file both of them are listed as returning an owned value.

[jyn514]

I think the difference is that generics_of uses ArenaCache, which returns a borrow? ugh

[jyn514]

Maybe the fix should be for rustdoc to turn <X as Y>::Assoc into the actual type that describes? That would make the standard library docs easier to read too.

[jyn514]

Re-opening this until I fix #79459 properly.