Default BackOffice number of results in list per page

[tehteh]

Hello,

i would like to change default number of results in list per page everywhere in Back Office(it is 50 by default).

I changed:

classes/helper/HelperList.php

/** @var array Number of results in list per page (used in select field) */
    protected $_pagination = array(300, 400, 500, 700);

classes/AdminTab.php

/** @var array Number of results in list per page (used in select field) */
    protected $_pagination = array(300, 400, 500, 700);

But anytime I log in, I need to change the number, because there are 50 results by default, even though there is no 50 number listed in selector.

Does anyone know how to change the default value?