Simplify an ObjectData field

compiler/rustc_trait_selection/src/traits/util.rs

@@ -243,12 +243,12 @@ pub fn upcast_choices<'tcx>(
 /// `object.upcast_trait_ref`) within the vtable for `object`.
 pub fn get_vtable_index_of_object_method<'tcx, N>(
     tcx: TyCtxt<'tcx>,
-    object: &super::ImplSourceObjectData<'tcx, N>,
+    object: &super::ImplSourceObjectData<N>,
     method_def_id: DefId,
 ) -> Option<usize> {
     // Count number of methods preceding the one we are selecting and
     // add them to the total offset.
-    tcx.own_existential_vtable_entries(object.upcast_trait_ref.def_id())
+    tcx.own_existential_vtable_entries(object.upcast_trait_def_id)
         .iter()
         .copied()
         .position(|def_id| def_id == method_def_id)