Private messages keep on coming

If a user sends a chat to another user who has logged out, then the message is put in the queue marked as not yet delivered. It will be delivered when the recipient logs back in.

However, if the private message module (https://www.drupal.org/project/privatemsg) is installed, then googlechat will deliver the chat message as a private message during a cron run. The message is not marked when this happens so a new private message is delivered every time cron runs.

The following patch changes this behaviour so that a chat message is only delivered as a private message if the privatemsg module is installed and a configuration setting is ticked.

Then, if a message is delivered as a private message, it is marked either as having been delivered as a private message or as having been delivered, depending on whether another configuration parameter that specifies whether to deliver only as a private message, or as both a private message and a chat message when the recipient logs back in, is checked.