code: @Direct
    @Override
    public void getStream(RowCursor cursor, 
                          Result<GetStreamResult> result)
    {
      long version = cursor.getVersion();
      
      PageLeafImpl leaf = getLeafByCursor(cursor);
      
      if (leaf == null) {
        result.ok(new GetStreamResult(false, null));
        return;
      }
      
      if (! leaf.get(cursor)) {
        result.ok(new GetStreamResult(false, null));
        return;
      }
  
      if (version == cursor.getVersion()) {
        result.ok(new GetStreamResult(true, null));
        return;
      }
      
      StreamSource ss = leaf.getStream(cursor, this);
      
      boolean isFound = ss != null;
  
      result.ok(new GetStreamResult(isFound, ss));
    }
docs: For cluster calls, returns a stream to the new value if the value
  has changed.