Don't require next-solver ProbeRef to be Copy

rust-analyzer would like to use a non-interned `Probe` there.

Also rename it to `Probe` for this reason.

compiler/rustc_middle/src/ty/context.rs

@@ -738,8 +738,8 @@ fn opaque_types_and_coroutines_defined_by(
         )
     }
 
-    type ProbeRef = &'tcx inspect::Probe<TyCtxt<'tcx>>;
-    fn mk_probe_ref(self, probe: inspect::Probe<Self>) -> &'tcx inspect::Probe<TyCtxt<'tcx>> {
+    type Probe = &'tcx inspect::Probe<TyCtxt<'tcx>>;
+    fn mk_probe(self, probe: inspect::Probe<Self>) -> &'tcx inspect::Probe<TyCtxt<'tcx>> {
         self.arena.alloc(probe)
     }
     fn evaluate_root_goal_for_proof_tree_raw(

compiler/rustc_next_trait_solver/src/solve/eval_ctxt/mod.rs

@@ -1275,7 +1275,7 @@ pub fn evaluate_root_goal_for_proof_tree_raw_provider<
 >(
     cx: I,
     canonical_goal: CanonicalInput<I>,
-) -> (QueryResult<I>, I::ProbeRef) {
+) -> (QueryResult<I>, I::Probe) {
     let mut inspect = inspect::ProofTreeBuilder::new();
     let canonical_result = SearchGraph::<D>::evaluate_root_goal_for_proof_tree(
         cx,
@@ -1284,7 +1284,7 @@ pub fn evaluate_root_goal_for_proof_tree_raw_provider<
         &mut inspect,
     );
     let final_revision = inspect.unwrap();
-    (canonical_result, cx.mk_probe_ref(final_revision))
+    (canonical_result, cx.mk_probe(final_revision))
 }
 
 /// Evaluate a goal to build a proof tree.

compiler/rustc_type_ir/src/interner.rs

@@ -1,3 +1,4 @@
+use std::borrow::Borrow;
 use std::fmt::Debug;
 use std::hash::Hash;
 use std::ops::Deref;
@@ -383,12 +384,12 @@ fn opaque_types_and_coroutines_defined_by(
         defining_anchor: Self::LocalDefId,
     ) -> Self::LocalDefIds;
 
-    type ProbeRef: Copy + Debug + Hash + Eq + Deref<Target = inspect::Probe<Self>>;
-    fn mk_probe_ref(self, probe: inspect::Probe<Self>) -> Self::ProbeRef;
+    type Probe: Debug + Hash + Eq + Borrow<inspect::Probe<Self>>;
+    fn mk_probe(self, probe: inspect::Probe<Self>) -> Self::Probe;
     fn evaluate_root_goal_for_proof_tree_raw(
         self,
         canonical_goal: CanonicalInput<Self>,
-    ) -> (QueryResult<Self>, Self::ProbeRef);
+    ) -> (QueryResult<Self>, Self::Probe);
 }
 
 /// Imagine you have a function `F: FnOnce(&[T]) -> R`, plus an iterator `iter`

compiler/rustc_type_ir/src/solve/inspect.rs

@@ -49,7 +49,7 @@ impl<I: Interner, T: Eq> Eq for State<I, T> {}
 pub struct GoalEvaluation<I: Interner> {
     pub uncanonicalized_goal: Goal<I, I::Predicate>,
     pub orig_values: Vec<I::GenericArg>,
-    pub final_revision: I::ProbeRef,
+    pub final_revision: I::Probe,
     pub result: QueryResult<I>,
 }