Enable TURN on the host when using WebRTC.

remoting/host/remoting_me2me_host.cc

Index: remoting/host/remoting_me2me_host.cc
diff --git a/remoting/host/remoting_me2me_host.cc b/remoting/host/remoting_me2me_host.cc
index e9245cfe593246b431367efc718b3276c58bf470..ef1c1b68ecf86d01d3d41e6c6a92bd44f43b559e 100644
--- a/remoting/host/remoting_me2me_host.cc
+++ b/remoting/host/remoting_me2me_host.cc
@@ -1510,7 +1510,7 @@ void HostProcess::StartHost() {
     network_settings.port_range.max_port = NetworkSettings::kDefaultMaxPort;
   }
 
-  scoped_refptr<protocol::TransportContext> transport_context =
+  scoped_refptr<protocol::TransportContext> ice_transport_context =
       new protocol::TransportContext(
           signal_strategy_.get(),
           make_scoped_ptr(new protocol::ChromiumPortAllocatorFactory()),
@@ -1518,6 +1518,8 @@ void HostProcess::StartHost() {
               context_->url_request_context_getter())),
           network_settings, protocol::TransportRole::SERVER);
 
+  scoped_refptr<protocol::TransportContext> webrtc_transport_context;
+
   scoped_ptr<protocol::SessionManager> session_manager(
       new protocol::JingleSessionManager(signal_strategy_.get()));
 
@@ -1530,13 +1532,22 @@ void HostProcess::StartHost() {
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
           kEnableWebrtcSwitchName)) {
     protocol_config->set_webrtc_supported(true);
+
+    webrtc_transport_context = new protocol::TransportContext(
+        signal_strategy_.get(),
+        make_scoped_ptr(new protocol::ChromiumPortAllocatorFactory()),
+        make_scoped_ptr(new ChromiumUrlRequestFactory(
+            context_->url_request_context_getter())),
+        network_settings, protocol::TransportRole::SERVER);
+    webrtc_transport_context->UseTurn(
+        ServiceUrls::GetInstance()->ice_config_url());
   }
   session_manager->set_protocol_config(std::move(protocol_config));
 
-  host_.reset(new ChromotingHost(desktop_environment_factory_.get(),
-                                 std::move(session_manager), transport_context,
-                                 context_->audio_task_runner(),
-                                 context_->video_encode_task_runner()));
+  host_.reset(new ChromotingHost(
+      desktop_environment_factory_.get(), std::move(session_manager),
+      ice_transport_context, webrtc_transport_context,
+      context_->audio_task_runner(), context_->video_encode_task_runner()));
 
   if (gnubby_auth_policy_enabled_ && gnubby_extension_supported_) {
     host_->AddExtension(make_scoped_ptr(new GnubbyExtension()));