Disable TCP ports in the default LibjingleTransportFactory() constructor.

remoting/protocol/libjingle_transport_factory.cc

Index: remoting/protocol/libjingle_transport_factory.cc
diff --git a/remoting/protocol/libjingle_transport_factory.cc b/remoting/protocol/libjingle_transport_factory.cc
index ca441af0f7005c0f3d8734a15a2291a90fb58508..f2d00a411f20bdd6cf205ef22aad6e8694a27ba2 100644
--- a/remoting/protocol/libjingle_transport_factory.cc
+++ b/remoting/protocol/libjingle_transport_factory.cc
@@ -320,6 +320,11 @@ LibjingleTransportFactory::LibjingleTransportFactory()
       port_allocator_(new cricket::BasicPortAllocator(
           network_manager_.get(), socket_factory_.get())),
       incoming_only_(false) {
+  port_allocator_->set_flags(
+      cricket::PORTALLOCATOR_DISABLE_TCP |
+      cricket::PORTALLOCATOR_DISABLE_STUN |
+      cricket::PORTALLOCATOR_DISABLE_RELAY |
+      cricket::PORTALLOCATOR_ENABLE_SHARED_UFRAG);
 }
 
 LibjingleTransportFactory::~LibjingleTransportFactory() {