command_process_create_cell: calls channel_send_destroy() for already exist circuit
command_process_create_cell
tries to check several conditions and can to call channel_send_destroy
for already exist circuit. channel_send_destroy
is more complex mechanism than sending of some cell as it happened before.
It shouldn't to call channel_send_destroy
if circ_id
already exist for chan
. It should to check circ_id
and drop if already exist and only then to check all another stuff.