Create a new preference which disables UDP protocol for WebRTC

content/renderer/p2p/port_allocator.h

Index: content/renderer/p2p/port_allocator.h
diff --git a/content/renderer/p2p/port_allocator.h b/content/renderer/p2p/port_allocator.h
index 3d1ae5fa161a85cc81d6ea66a3e2f8ea9b1631f2..fc1f3dc4ff667c4cea9b5bb6bb08697940108837 100644
--- a/content/renderer/p2p/port_allocator.h
+++ b/content/renderer/p2p/port_allocator.h
@@ -38,6 +38,9 @@ class P2PPortAllocator : public cricket::BasicPortAllocator {
     // Disable TCP-based transport when set to true.
     bool disable_tcp_transport;
 
+    // Disable UPD-based transport when set to true.
+    bool disable_udp_transport;
+
     // Disable binding to individual NICs when set to false.
     bool enable_multiple_routes;
   };