Description:
------------
The reference coordinates values changed from 4.3.6 to 
4.3.8 on imagettfbbox() ? 
 
( gd 2.0.26 ) 
 

Reproduce code:
---------------
<pre>
<?php
$font_dir = $_SERVER["DOCUMENT_ROOT"]."/fonts";
$box = imagettfbbox(18,0,$font_dir."/ariblk.ttf","test");
var_dump($box);
?>
</pre>

Expected result:
----------------
array(8) { 
  [0]=> 
  int(0) 
  [1]=> 
  int(-1) 
  [2]=> 
  int(52) 
  [3]=> 
  int(-1) 
  [4]=> 
  int(52) 
  [5]=> 
  int(-19) 
  [6]=> 
  int(0) 
  [7]=> 
  int(-19) 
} 
 

Actual result:
--------------
array(8) { 
  [0]=> 
  int(0) 
  [1]=> 
  int(-20) 
  [2]=> 
  int(53) 
  [3]=> 
  int(-20) 
  [4]=> 
  int(53) 
  [5]=> 
  int(0) 
  [6]=> 
  int(0) 
  [7]=> 
  int(0) 
}