MFB: Add test case for #44849

ext/gd/tests/bug44849.phpt

@@ -0,0 +1,13 @@
+--TEST--
+Bug #44849 (imagecolorclosesthwb is not available on Windows)
+--SKIPIF--
+<?php
+	if(!extension_loaded('gd')){ die('skip: gd extension not available'); }
+	if(strtoupper(substr(PHP_OS, 0, 3)) != 'WIN'){ die('skip: not a Windows operating system'); }
+?>
+--FILE--
+<?php
+	var_dump(function_exists('imagecolorclosesthwb'));
+?>
+--EXPECTF--
+bool(true)