anchor.diff:      if (normalize) {
         int length = _Utils.arrayLength(bounds);
         int count = 0;
  -      Object? typeArguments = JS('', 'new Array(#)', length);
  +      Object? typeArguments = _Utils.newArrayOrEmpty(length);
         for (int i = 0; i < length; i++) {
           Rti bound = _Utils.asRti(_Utils.arrayAt(bounds, i));
           if (Rti._getKind(bound) == Rti.kindNever) {
  
positive.code: 
    static JSArray arrayConcat(Object? a1, Object? a2) =>
        JS('JSArray', '#.concat(#)', a1, a2);
  
    static void arrayPush(Object? array, Object? value) {
      JS('', '#.push(#)', array, value);
    }
  
    static String substring(String s, int start, int end) =>
        JS('String', '#.substring(#, #)', s, start, end);
  
negative.code:     }
    }
  
    static Object? newArrayOrEmpty(int length) => length > 0
        ? JS('', 'new Array(#)', length)
        : _Universe.sharedEmptyArray(_theUniverse());
  
    static bool isArray(Object? o) => JS('bool', 'Array.isArray(#)', o);
  
    static int arrayLength(Object? array) => JS('int', '#.length', array);
  