Description:
------------
When I try to generate chords, I only get the outer border (not the arc) in no-
fill mode and if I want to generate a filled chord, it appears to fill the outer 
part of it, producing a triangle instead of a chord

Test script:
---------------
<?php

$width = 400;
$height = 300;

$canvas = imagecreatetruecolor($width, $height);

imagefilledrectangle($canvas, 0, 0, $width, $height, imagecolorallocatealpha($canvas, 0, 0, 0, 0));

imagefilledarc($canvas, 200, 150, $width / 2, $height / 2, 45, 135, imagecolorallocatealpha($canvas, 255, 255, 255, 0), IMG_ARC_CHORD /* | IMG_ARC_NOFILL */);

imagejpeg($canvas, '/path/to/chord.jpg');

Expected result:
----------------
Chord = pie - triangle

Actual result:
--------------
I am getting pie - chord (only the triangle)