* Load or initialize $authAction, $authRequests and $subPage.
* Subclasses should call this from execute() or otherwise ensure the variables are initialized.
* @param string $subPage Subpage of the special page.
* Load or initialize $authAction, $authRequests and $subPage.
* Subclasses should call this from execute() or otherwise ensure the variables are initialized.
* @param string $subPage Subpage of the special page.