Inline MemCategorization into ExprUseVisitor

Author: compiler-errors

clippy_lints/src/operators/assign_op_pattern.rs

@@ -120,7 +120,7 @@ fn imm_borrows_in_expr(cx: &LateContext<'_>, e: &hir::Expr<'_>) -> HirIdSet {
 
     let mut s = S(HirIdSet::default());
     let infcx = cx.tcx.infer_ctxt().build();
-    let mut v = ExprUseVisitor::new(
+    let v = ExprUseVisitor::new(
         &mut s,
         &infcx,
         cx.tcx.hir().body_owner_def_id(cx.enclosing_body.unwrap()),
@@ -152,7 +152,7 @@ fn mut_borrows_in_expr(cx: &LateContext<'_>, e: &hir::Expr<'_>) -> HirIdSet {
 
     let mut s = S(HirIdSet::default());
     let infcx = cx.tcx.infer_ctxt().build();
-    let mut v = ExprUseVisitor::new(
+    let v = ExprUseVisitor::new(
         &mut s,
         &infcx,
         cx.tcx.hir().body_owner_def_id(cx.enclosing_body.unwrap()),

clippy_lints/src/unwrap.rs

@@ -253,7 +253,7 @@ impl<'a, 'tcx> UnwrappableVariablesVisitor<'a, 'tcx> {
             };
 
             let infcx = self.cx.tcx.infer_ctxt().build();
-            let mut vis = ExprUseVisitor::new(
+            let vis = ExprUseVisitor::new(
                 &mut delegate,
                 &infcx,
                 cond.hir_id.owner.def_id,