Add check to prevent TURN usage if the protocol is not allowed.

webrtc/p2p/client/basicportallocator.cc

Index: webrtc/p2p/client/basicportallocator.cc
diff --git a/webrtc/p2p/client/basicportallocator.cc b/webrtc/p2p/client/basicportallocator.cc
index 2a9ee3b8ba063cdb987dc25cf89c680a6b67280e..55e0eb3c3f9d27da89cb5e5b1e617e053c5afea9 100644
--- a/webrtc/p2p/client/basicportallocator.cc
+++ b/webrtc/p2p/client/basicportallocator.cc
@@ -983,6 +983,13 @@ void AllocationSequence::CreateTurnPort(const RelayServerConfig& config) {
   for (relay_port = config.ports.begin();
        relay_port != config.ports.end(); ++relay_port) {
     TurnPort* port = NULL;
+
+    // Skip the turn server that uses disallowed protocol.

[pthatcher1, 2015/08/25 22:59:30]

Might be more clear as "Skip UDP connections to relay servers if it's
disallowed".

+    if (IsFlagSet(PORTALLOCATOR_DISABLE_TURN_OVER_UDP) &&
+        relay_port->proto == PROTO_UDP) {
+      continue;
+    }
+
     // Shared socket mode must be enabled only for UDP based ports. Hence
     // don't pass shared socket for ports which will create TCP sockets.
     // TODO(mallinath) - Enable shared socket mode for TURN ports. Disabled