Bug 1744 fixed : Incorrect use of timezone with SQLite

Fixed anti-flood system.

Merge from trunk

git-svn-id: http://piwigo.org/svn/branches/2.1@6605 68402e56-0260-453c-a942-63ccdbb3a9ee

include/dblayer/functions_mysql.inc.php

@@ -560,7 +560,6 @@ function boolean_to_string($var)
  *
  */
 
-
 function pwg_db_get_recent_period_expression($period, $date='CURRENT_DATE')
 {
   if ($date!='CURRENT_DATE')
@@ -580,6 +579,11 @@ SELECT '.pwg_db_get_recent_period_expression($period);
   return $d;
 }
 
+function pwg_db_get_flood_period_expression($seconds)
+{
+  return 'SUBDATE(now(), INTERVAL '.$seconds.' SECOND)';
+}
+
 function pwg_db_get_hour($date) 
 {
   return 'hour('.$date.')';