98e186c71c
The only thing the physical socket server was used for was "Wait"/"WakeUp", but it could be replaced by a simple rtc::Event. So, removing this dependency makes things less confusing; the fact that VirtualSocketServer takes a PhysicalSocketServer may lead someone to think it uses real sockets internally, when it doesn't. BUG=None Review-Url: https://codereview.webrtc.org/2883313003 Cr-Commit-Position: refs/heads/master@{#18172}