Fixed multiple bugs related to undefined variables

[jpbellona]

Using wp-recaptcha 3.1.6 with WP version 3.4 (all bugs existed also in 3.3.2)

All bugs related to undefined variables.

1. WP-recaptcha throws errors of undefined variables on all page loads.
   PHP Notice: Undefined variable: rcommentid in /wp-content/plugins/wp-recaptcha/recaptcha.php on line 482
   PHP Notice: Undefined variable: rchash in /wp-content/plugins/wp-recaptcha/recaptcha.php on line 484
   FIX: Added in a check
   if (!empty($_REQUEST['rcommentid']))
   $comment_id = $_REQUEST['rcommentid'];

    if (!empty($_REQUEST['rchash']))
       $comment_hash = $_REQUEST['rchash'];

1. on a single post with comment form
   PHP Notice: Undefined index: rerror in /wp-content/plugins/wp-recaptcha/recaptcha.php on line 401
   FIX: Added in a check
   if (isset($_GET['rerror'])) {
   $escaped_error = htmlentities($_GET['rerror'], ENT_QUOTES);
   }

2. on the WP login page (using wp-recaptcha)
   PHP Notice: Undefined index: rerror in /var/www/html/student/bellona/public_html/chinavine2/wp-content/plugins/wp-recaptcha/recaptcha.php on line 278
   FIX: Added in a check
   if (isset($_GET['rerror'])) {
   $escaped_error = htmlentities($_GET['rerror'], ENT_QUOTES);
   } else {
   $escaped_error = '';
   }

3. after logging a comment
   PHP Notice: Undefined variable: needed_capability in /var/www/html/student/bellona/public_html/chinavine2/wp-content/plugins/wp-recaptcha/recaptcha.php on line 439
   FIX: Nested the conditional for returning the comment since it requires a defined variable

       if ($this->options['bypass_for_registered_users'] && $this->options['minimum_bypass_level']) {
           $needed_capability = $this->options['minimum_bypass_level'];
   
           if (($needed_capability && current_user_can($needed_capability)) || !$this->options['show_in_comments'])
               return $comment_data;
       }
   

That's it. Thanks for your work.