propose fix for bcit-ci#6122

propose fix for bcit-ci#6122 unsure if this is a valid fix, my code (while using this function) doesn't actually use this function.

$filedata will return bool(false) on
 "/var/www/html/project/application/cache/index.html"

Causing the error posted in the issue.

system/helpers/file_helper.php

@@ -229,8 +229,11 @@ function get_dir_file_info($source_dir, $top_level_only = TRUE, $_recursion = FA
 				elseif ($file[0] !== '.')
 				{
 					$filedata = get_dir_file_info($source_dir.$file);
-					$filedata['relative_path'] = $relative_path;
-					$_filedata[] = $filedata;
+					if ($filedata)
+					{
+						$filedata['relative_path'] = $relative_path;
+						$_filedata[] = $filedata;
+					}
 				}
 			}