Remove VirtualSocketServer's dependency on PhysicalSocketServer.

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}

webrtc/p2p/base/tcpport_unittest.cc

diff --git a/webrtc/p2p/base/tcpport_unittest.cc b/webrtc/p2p/base/tcpport_unittest.cc
index 7b354df..cc3f9ad 100644
--- a/webrtc/p2p/base/tcpport_unittest.cc
+++ b/webrtc/p2p/base/tcpport_unittest.cc
@@ -11,7 +11,6 @@
 #include <memory>
 
 #include "webrtc/base/gunit.h"
-#include "webrtc/base/physicalsocketserver.h"
 #include "webrtc/base/thread.h"
 #include "webrtc/base/virtualsocketserver.h"
 #include "webrtc/p2p/base/basicpacketsocketfactory.h"
@@ -31,8 +30,7 @@
 class TCPPortTest : public testing::Test, public sigslot::has_slots<> {
  public:
   TCPPortTest()
-      : pss_(new rtc::PhysicalSocketServer),
-        ss_(new rtc::VirtualSocketServer(pss_.get())),
+      : ss_(new rtc::VirtualSocketServer()),
         main_(ss_.get()),
         network_("unittest", "unittest", rtc::IPAddress(INADDR_ANY), 32),
         socket_factory_(rtc::Thread::Current()),
@@ -63,7 +61,6 @@
   }
 
  protected:
-  std::unique_ptr<rtc::PhysicalSocketServer> pss_;
   std::unique_ptr<rtc::VirtualSocketServer> ss_;
   rtc::AutoSocketServerThread main_;
   rtc::Network network_;