anchor.diff:        }
   
         final populatePages = page * pageSize;
  -      if (desc) {
  +      if (_desc) {
           list.removeRange(populatePages, size - populatePages);
         } else {
           list.removeRange(0, size - populatePages);
  
positive.code:     _selected = item;
    }
  
  }
  
  
negative.code:     // the first item in the visible list
      var pair = list[page * pageSize];
  
      var req = ds.ParamRangeKey.$create(_desc,
        limit: math.min(pageSize, list.length),
        startKey: _desc ? util.incrementKey(pair.orig.key) : util.decrementKey(pair.orig.key),
      );
  
      _fetchTs = now;
  