check whether $uri['host'] isset in common.inc

in common.inc, row 480:
$host = $uri['host'] . ($port != 80 ? ':'. $port : '');

may generate a PHP notice that $uri['host'] is undefined. I suggest to check for it:

if(isset($uri['host'])){
$host = $uri['host'] . ($port != 80 ? ':'. $port : '');
}