Disabling browser auto-complete w/ php & js

Hello,

I am trying to follow the instructions spelled out in this thread,
http://ww.wp.xz.cn/support/topic/disable-password-auto-complete?replies=8
and am running into problems with a syntax error.

To summarize, I added this to functions.php

function kill_autocomplete() {
   wp_register_script('kill-ac',
       get_template_directory_uri() . '/js/autocompleteoff.js',
       array('jquery'),
       '1.0' );
   wp_enqueue_script('kill-ac');
}
add_action('wp_enqueue_scripts', 'kill_autocomplete');

and added a file named autocompleteoff.js to wp-includes/js/ that contained this line of code
jQuery('#user_pass').attr('autocomplete','off');

After uploading these files I am getting a syntax error from the php, which is not surprising since I am basically cutting and pasting stuff in Simple Text. Here is the message…

Fatal error: Call to undefined function add_action() in /home/content/s/p/a/spaceheat/html/WordPress/wp-includes/functions.php on line 4559

Any idea what might be going wrong?

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