Merge pull request xenserver#1311 from GaborApatiNagy/master_CA-232294

CA-232294: Can't connect if an Add Server dialog has been cancelled before

Author: Mihaela Stoica

XenAdmin/Dialogs/AddServerDialog.Designer.cs

@@ -337,6 +337,12 @@ private void labelError_TextChanged(object sender, EventArgs e)
         {
             pictureBoxError.Visible = labelError.Visible = (labelError.Text != "");
         }
+
+        private void AddServerDialog_FormClosing(object sender, FormClosingEventArgs e)
+        {
+            if (connection != null)
+                XenConnectionUI.connectionDialogs.Remove(connection);
+        }
     }
 
     public class CachePopulatedEventArgs : EventArgs