Standardize and update code

htdocs/admin/dict.php

@@ -592,7 +592,7 @@ if ($id == 10)
  * Actions
  */
 
-if (GETPOST('button_removefilter') || GETPOST('button_removefilter.x') || GETPOST('button_removefilter_x'))
+if (GETPOST('button_removefilter', 'alpha') || GETPOST('button_removefilter.x', 'alpha') || GETPOST('button_removefilter_x', 'alpha'))
 {
     $search_country_id = '';
     $search_code = '';

htdocs/contact/list.php

@@ -202,7 +202,7 @@ if (empty($reshook))
 	include DOL_DOCUMENT_ROOT.'/core/actions_changeselectedfields.inc.php';
 
 	// Did we click on purge search criteria ?
-	if (GETPOST('button_removefilter_x') || GETPOST('button_removefilter.x') || GETPOST('button_removefilter'))	// All tests are required to be compatible with all browsers
+	if (GETPOST('button_removefilter_x', 'alpha') || GETPOST('button_removefilter.x', 'alpha') || GETPOST('button_removefilter', 'alpha'))	// All tests are required to be compatible with all browsers
 	{
 		$sall="";
 		$search_id='';