Skip confirmation dialog when deleting a contact from a source that supports undelete operations

program/include/rcmail.php

@@ -483,7 +483,8 @@ class rcmail
         'name'     => rcube_label('personaladrbook'),
         'groups'   => $this->address_books['0']->groups,
         'readonly' => $this->address_books['0']->readonly,
-        'autocomplete' => in_array('sql', $autocomplete)
+        'autocomplete' => in_array('sql', $autocomplete),
+        'undelete' => $this->address_books['0']->undelete && $this->config->get('undo_timeout'),
       );
     }
 

program/js/app.js

@@ -3994,7 +3994,8 @@ function rcube_webmail()
   {
     // exit if no mailbox specified or if selection is empty
     var selection = this.contact_list.get_selection();
-    if (!(selection.length || this.env.cid) || !confirm(this.get_label('deletecontactconfirm')))
+    var undelete = this.env.address_sources[this.env.source].undelete;
+    if (!(selection.length || this.env.cid) || (!undelete && !confirm(this.get_label('deletecontactconfirm'))))
       return;
 
     var id, n, a_cids = [], qs = '';