changed line #298 for fixing an issue when saving static google maps

I only changed line #298 in file \components\com_fabrik\helpers\image.php

from
file_put_contents($cacheFile, file_get_contents($src));
to
$file=uniqid('map_');$cacheFile = $folder . $file;file_put_contents($cacheFile, file_get_contents($src));

But all the file content has been marked has changed. 
Don't know how to avoid that