Rollup merge of #147713 - cjgillot:where-cfg, r=fmease

Retire ast::TyAliasWhereClauses. `ast::TyAliasWhereClauses` is a tentative to avoid forgetting predicates when manipulating the AST. It is incompatible with `cfg` attributes on where clauses. This PR uses a regular `WhereClause` for the "second" clause. Fixes #138010 cc #138037

Author: jhpratt

clippy_utils/src/ast_utils/mod.rs

@@ -562,22 +562,23 @@ pub fn eq_foreign_item_kind(l: &ForeignItemKind, r: &ForeignItemKind) -> bool {
  defaultness: ld,
  ident: li,
  generics: lg,
- where_clauses: _,
+ after_where_clause: lw,
  bounds: lb,
  ty: lt,
  }),
  TyAlias(box ast::TyAlias {
  defaultness: rd,
  ident: ri,
  generics: rg,
- where_clauses: _,
+ after_where_clause: rw,
  bounds: rb,
  ty: rt,
  }),
  ) => {
  eq_defaultness(*ld, *rd)
  && eq_id(*li, *ri)
  && eq_generics(lg, rg)
+ && over(&lw.predicates, &rw.predicates, eq_where_predicate)
  && over(lb, rb, eq_generic_bound)
  && both(lt.as_ref(), rt.as_ref(), |l, r| eq_ty(l, r))
  },
@@ -645,22 +646,23 @@ pub fn eq_assoc_item_kind(l: &AssocItemKind, r: &AssocItemKind) -> bool {
  defaultness: ld,
  ident: li,
  generics: lg,
- where_clauses: _,
+ after_where_clause: lw,
  bounds: lb,
  ty: lt,
  }),
  Type(box TyAlias {
  defaultness: rd,
  ident: ri,
  generics: rg,
- where_clauses: _,
+ after_where_clause: rw,
  bounds: rb,
  ty: rt,
  }),
  ) => {
  eq_defaultness(*ld, *rd)
  && eq_id(*li, *ri)
  && eq_generics(lg, rg)
+ && over(&lw.predicates, &rw.predicates, eq_where_predicate)
  && over(lb, rb, eq_generic_bound)
  && both(lt.as_ref(), rt.as_ref(), |l, r| eq_ty(l, r))
  },