Izmjenjena struktura, dodan backand

web/node_modules/core-js/modules/es6.date.to-string.js

@@ -0,0 +1,10 @@
+var DateProto    = Date.prototype
+  , INVALID_DATE = 'Invalid Date'
+  , TO_STRING    = 'toString'
+  , $toString    = DateProto[TO_STRING];
+if(new Date(NaN) + '' != INVALID_DATE){
+  require('./$.redefine')(DateProto, TO_STRING, function toString(){
+    var value = +this;
+    return value === value ? $toString.call(this) : INVALID_DATE;
+  });
+}