Don't rely on include_path to include files.

Always use dirname() or, once available, ABSPATH.

props ketwaroo, hakre.
fixes #17092.

Built from https://develop.svn.wordpress.org/trunk@25616


git-svn-id: http://core.svn.wordpress.org/trunk@25533 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/user/credits.php

@@ -8,6 +8,6 @@
  */
 
 /** Load WordPress Administration Bootstrap */
-require_once( './admin.php' );
+require_once( dirname( __FILE__ ) . '/admin.php' );
 
-require( '../credits.php' );
+require( ABSPATH . 'wp-admin/credits.php' );