Auto merge of #85020 - lrh2000:named-upvars, r=tmandry

Name the captured upvars for closures/generators in debuginfo

Previously, debuggers print closures as something like
```
y::main::closure-0 (0x7fffffffdd34)
```
The pointer actually references to an upvar. It is not very obvious, especially for beginners.

It's because upvars don't have names before, as they are packed into a tuple. This PR names the upvars, so we can expect to see something like
```
y::main::closure-0 {_captured_ref__b: 0x[...]}
```

r? `@tmandry`
Discussed at https://github.com/rust-lang/rust/pull/84752#issuecomment-831639489 .

compiler/rustc_middle/src/ty/mod.rs

@@ -16,7 +16,6 @@ pub use self::IntVarValue::*;
 pub use self::Variance::*;
 pub use adt::*;
 pub use assoc::*;
-pub use closure::*;
 pub use generics::*;
 pub use vtable::*;
 
@@ -55,6 +54,12 @@ pub use rustc_type_ir::*;
 
 pub use self::binding::BindingMode;
 pub use self::binding::BindingMode::*;
+pub use self::closure::{
+    is_ancestor_or_same_capture, place_to_string_for_capture, BorrowKind, CaptureInfo,
+    CapturedPlace, ClosureKind, MinCaptureInformationMap, MinCaptureList,
+    RootVariableMinCaptureList, UpvarBorrow, UpvarCapture, UpvarCaptureMap, UpvarId, UpvarListMap,
+    UpvarPath, CAPTURE_STRUCT_LOCAL,
+};
 pub use self::consts::{Const, ConstInt, ConstKind, InferConst, ScalarInt, Unevaluated, ValTree};
 pub use self::context::{
     tls, CanonicalUserType, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations,
@@ -1980,6 +1985,7 @@ pub fn ast_uint_ty(uty: UintTy) -> ast::UintTy {
 }
 
 pub fn provide(providers: &mut ty::query::Providers) {
+    closure::provide(providers);
     context::provide(providers);
     erase_regions::provide(providers);
     layout::provide(providers);