[Serusers] Cancel'ing filure_route

[Dmitry Isakbayev]

Hello,

I need help understanding how to handle "CANCEL" messages.  Here is the 
case -
 1 Proxy rebuilds URI, sets 'failure_route', and executes 't_relay'
 2 't_realy' times out and the proxy executes 'failure_route' after the 
fr_timer hits

If the OUI cancels the call between steps 1 and 2, the proxy still executes 
the 'failure_route' after the fr_timer hits.

Can I cancel any "t_on_failure" logic after receiving a CANCEL message?

Or, while in in the 'failre_rout' block, can I figure out that there was a 
CANCEL message?

Thank You,
Dmitry