Send 200Ok to server if message we can't decrypt to avoid useless retransmission + adaptation of tests to this behavior

fix problem with video device being set many times for nothing in the property box, which creates graph stop/start when in a video call

Perform an ICE reset instead of an ICE restart when recovering from a connection loss (it has the effect to also clear the previous local candidates).

-add useragent to remote provisioning http request