config_item() to return NULL instead of FALSE for non-existing items

Close #3001
Close #3232
Related: #3244
diff --git a/system/core/Input.php b/system/core/Input.php
index ada9fc6..9ae2f6d 100644
--- a/system/core/Input.php
+++ b/system/core/Input.php
@@ -353,7 +353,7 @@
 			$path = config_item('cookie_path');
 		}
 
-		if ($secure === FALSE && config_item('cookie_secure') !== FALSE)
+		if ($secure === FALSE && config_item('cookie_secure') === TRUE)
 		{
 			$secure = config_item('cookie_secure');
 		}