Bug #21314: maintains a separate snowflake connect loop per SOCKS
connection. This way, if Tor decides to stop using Snowflake, Snowflake
will stop using the client's network.
Do it as a side effect of NewWebRTCPeer.
Remove WebRTCPeer tests as they currently require invasively modifying
internal fields at different stages of construction.
The other interfaces in client/lib/interfaces.go exist for the purpose
of running tests, but not Snowflake. Existing code would not have worked
with other types anyway, because it does unchecked .(*WebRTCPeer)
conversions.
We are no longer checking for nil BrokerChannels in Catch because this
case is caught from the return values of NewBrokerChannel. This change
caused a no longer necessary unit test to hang.
There were a few tests that needed refreshing since the introduction of
the pion library. Also added a few tests for the ICE server parsing
function in the client.
Modified the snowflake client to use pion/webrtc as the webrtc library.
This involved a few small changes to match function signatures as well
as several larger ones:
- OnNegotiationNeeded is no longer supported, so CreateOffer and
SetLocalDescription have been moved to a go routine called after the
other peer connection callbacks are set
- We need our own deserialize/serialize functions
- We need to use a SettingEngine in order to access the
OnICEGatheringStateChange callback
