Problem in the tny-camel-send-queue when sending messages

[Sergio Villar Senin <svillar igalia com>]

Hi,

I've just found that "msg-sent" signal is issued twice by the
TnyCamelSendQueue when a message has been successfully sent. The update
method of the sentbox observer (tny_camel_send_queue_update) is called
several times each time a message is sent and this first condition

258: if (changed & TNY_FOLDER_CHANGE_CHANGED_ADDED_HEADERS)

is fulfilled twice, I mean, the method receives two TnyChange objects in
two different calls with the ADDED_HEADERS flag, so it gets the message
twice (it calls tny_folder_get_msg_async) and so it emits the "msg-sent"
signal twice.

This indeed could lead to problems in client applications.

Br