Replace `#[allow]` with `#[expect]` in Clippy
Hey `@rust-lang/clippy,` `@Alexendoo,` `@dswij,` I'm currently working on the expect attribute as defined in [Rust RFC 2383](https://rust-lang.github.io/rfcs/2383-lint-reasons.html). With that, an `#[allow]` attribute can be replaced with a `#[expect]` attribute that suppresses the lint, but also emits a warning, if the lint isn't emitted in the expected scope.
With this PR I would like to test the attribute on a project scale and Clippy obviously came to mind. This PR replaces (almost) all `#[allow]` attributes in `clippy_utils` and `clippy_lints` with the `#[expect]` attribute. I was also able to remove some allows since, the related FPs have been fixed 🎉.
My question is now, are there any concerns regarding this? It's still okay to add normal `#[allow]` attributes, I see the need to nit-pick about that in new PRs, unless it's actually a FP. Also, I would not recommend using `#[expect]` in tests, as changes to a lint could the trigger the expect attribute in other files.
Additionally, I've noticed that Clippy has a bunch of `#[allow(clippy::too_many_lines)]` attributes. Should we maybe allow the lint all together or increase the threshold setting? To me, it seems like we mostly just ignore it in our code. 😅🙃
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changelog: none
r? `@flip1995` (I've requested you for now, since you're also helping with reviewing the expect implementation. You are welcome to delegate this PR, even if it should be a simple review 🙃 )
StructField -> FieldDef ("field definition")
Field -> ExprField ("expression field", not "field expression")
FieldPat -> PatField ("pattern field", not "field pattern")
Also rename visiting and other methods working on them.
By moving `{known,used}_attrs` from `SessionGlobals` to `Session`. This
means they are accessed via the `Session`, rather than via TLS. A few
`Attr` methods and `librustc_ast` functions are now methods of
`Session`.
All of this required passing a `Session` to lots of functions that didn't
already have one. Some of these functions also had arguments removed, because
those arguments could be accessed directly via the `Session` argument.
`contains_feature_attr()` was dead, and is removed.
Some functions were moved from `librustc_ast` elsewhere because they now need
to access `Session`, which isn't available in that crate.
- `entry_point_type()` --> `librustc_builtin_macros`
- `global_allocator_spans()` --> `librustc_metadata`
- `is_proc_macro_attr()` --> `Session`
For consistency with `Attribute::has_name` which doesn't mark the attribute as used either.
Replace all uses of `check_name` with `has_name` outside of rustc
