Remove yields_in_scope from the scope tree.

compiler/rustc_mir_build/src/builder/expr/as_rvalue.rs

@@ -171,9 +171,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 this.diverge_from(block);
                 block = success;
 
-                // The `Box<T>` temporary created here is not a part of the HIR,
-                // and therefore is not considered during coroutine auto-trait
-                // determination. See the comment about `box` at `yield_in_scope`.
                 let result = this.local_decls.push(LocalDecl::new(expr.ty, expr_span));
                 this.cfg
                     .push(block, Statement::new(source_info, StatementKind::StorageLive(result)));