Convert a &Lrc<T> argument to Lrc<T>.

It's slightly simpler.

compiler/rustc_infer/src/infer/mod.rs

@@ -776,7 +776,7 @@ pub fn member_constraint(
         definition_span: Span,
         hidden_ty: Ty<'tcx>,
         region: ty::Region<'tcx>,
-        in_regions: &Lrc<Vec<ty::Region<'tcx>>>,
+        in_regions: Lrc<Vec<ty::Region<'tcx>>>,
     ) {
         self.inner.borrow_mut().unwrap_region_constraints().member_constraint(
             key,

compiler/rustc_infer/src/infer/opaque_types/mod.rs

@@ -359,7 +359,15 @@ pub fn register_member_constraints(
         // not currently sound until we have existential regions.
         concrete_ty.visit_with(&mut ConstrainOpaqueTypeRegionVisitor {
             tcx: self.tcx,
-            op: |r| self.member_constraint(opaque_type_key, span, concrete_ty, r, &choice_regions),
+            op: |r| {
+                self.member_constraint(
+                    opaque_type_key,
+                    span,
+                    concrete_ty,
+                    r,
+                    choice_regions.clone(),
+                )
+            },
         });
     }
 }

compiler/rustc_infer/src/infer/region_constraints/mod.rs

@@ -522,7 +522,7 @@ pub(super) fn member_constraint(
         definition_span: Span,
         hidden_ty: Ty<'tcx>,
         member_region: ty::Region<'tcx>,
-        choice_regions: &Lrc<Vec<ty::Region<'tcx>>>,
+        choice_regions: Lrc<Vec<ty::Region<'tcx>>>,
     ) {
         debug!("member_constraint({:?} in {:#?})", member_region, choice_regions);
 
@@ -535,7 +535,7 @@ pub(super) fn member_constraint(
             definition_span,
             hidden_ty,
             member_region,
-            choice_regions: choice_regions.clone(),
+            choice_regions,
         });
     }