[zendframework/zendframework#3376] Replace PCRE /e modifier with preg…

…_replace_callback()

- Replaced usage of preg_replace with "/e" modifier with
  preg_replace_callback() using a closure

src/Converter/Converter.php

@@ -64,7 +64,9 @@ public static function ascToHex32($string)
      */
     public static function hex32ToAsc($string)
     {
-        $string = preg_replace('/\\\([0-9A-Fa-f]{2})/e', "''.chr(hexdec('\\1')).''", $string);
+        $string = preg_replace_callback('/\\\([0-9A-Fa-f]{2})/', function ($matches) {
+            return chr(hexdec($matches[1]));
+        }, $string);
         return $string;
     }