add additional checks to transformers

lib/6to5/transformation/transformers/es6/object-super.js

@@ -4,6 +4,10 @@ var ReplaceSupers = require("../../helpers/replace-supers");
 var util          = require("../../../util");
 var t             = require("../../../types");
 
+exports.check = function (node, parent) {
+  return t.isIdentifier(node, { name: "super" });
+};
+
 exports.Property = function (node, parent, scope, file) {
   if (!node.method) return;
 

lib/6to5/transformation/transformers/validation/no-for-in-of-assignment.js

@@ -2,6 +2,8 @@
 
 var t = require("../../../types");
 
+exports.check = t.isFor;
+
 exports.ForInStatement =
 exports.ForOfStatement = function (node, parent, scope, file) {
   var left = node.left;

lib/6to5/transformation/transformers/validation/setters.js

@@ -1,5 +1,9 @@
 "use strict";
 
+exports.check = function (node) {
+  return node.kind === "set";
+};
+
 exports.MethodDefinition =
 exports.Property = function (node, parent, scope, file) {
   if (node.kind === "set" && node.value.params.length !== 1) {