SUBSCRIBE session restarts expire timer after each NOTIFY

What steps will reproduce the problem?
1. Subscribe to any presence status
2. If there're any status changes the SUBSCRIBE session will be terminated by 
SIP-server
3. Wait a little bit more, sipml5 will try to renew SUBSCRIBE after "expires/2" 
since the last NOTIFY

What is the expected output? What do you see instead?

I expect that "expires" should count intervals between renewal of SUBSCRIBE, 
not since the last NOTIFY from server.

What version of the product are you using? On what operating system?

SIPML5 API version = 1.4.217, Asterisk 11.8.1, Firefox 24.3.0, Gentoo Linux 
(kernel 3.10.25)

Please provide any additional information below.

If presence status was not changed during expires interval or it was changed 
and remaining time to the next renewal is more than expires/2 then SUBSCRIBE 
sessions renewed successfully.

Sample SUBSCRIBE session flow (with expires = 200):
15:03:03 - SUBSCRIBE session started
15:03:03 - NOTIFY presence status received (in response to SUBSCRIBE)
15:04:43 - SUBSCRIBE renewal sent
15:04:43 - NOTIFY presence status received (in response to SUBSCRIBE)
15:05:07 - NOTIFY presence status received
15:06:47 - SUBSCRIBE renewal sent
15:06:47 - NOTIFY presence status received (in response to SUBSCRIBE)
15:08:07 - NOTIFY presence status received
15:08:08 - NOTIFY presence status received
15:08:13 - NOTIFY presence status received
15:09:30 - NOTIFY presence status received
15:09:42 - NOTIFY presence status received
15:10:17 - NOTIFY with termination received (210 seconds since 15:06:47)
15:11:57 - SUBSCRIBE renewal sent
15:11:57 - 481 Call/Transaction Does Not Exist received

Original issue reported on code.google.com by gpuzan...@gmail.com on 16 Apr 2014 at 11:33

Attachments:

acappel01 / sipml5

SUBSCRIBE session restarts expire timer after each NOTIFY #176