Create a new preference which disables UDP protocol for WebRTC

content/renderer/media/webrtc/peer_connection_dependency_factory.cc

Index: content/renderer/media/webrtc/peer_connection_dependency_factory.cc
diff --git a/content/renderer/media/webrtc/peer_connection_dependency_factory.cc b/content/renderer/media/webrtc/peer_connection_dependency_factory.cc
index 0fecca7c3e8001fb5b3aa4d5a41e3bbcb92aeb83..0d5fec8d913a411022b32b12e32f3ee479e00176 100644
--- a/content/renderer/media/webrtc/peer_connection_dependency_factory.cc
+++ b/content/renderer/media/webrtc/peer_connection_dependency_factory.cc
@@ -122,12 +122,14 @@ class P2PPortAllocatorFactory : public webrtc::PortAllocatorFactoryInterface {
                           rtc::NetworkManager* network_manager,
                           rtc::PacketSocketFactory* socket_factory,
                           const GURL& origin,
-                          bool enable_multiple_routes)
+                          bool enable_multiple_routes,
+                          bool enable_udp_transport)

[pthatcher2, 2015/08/25 23:12:34]

Can we make some kind of struct to contain the various options
(origin+enable_multiple_routes+enable_udp_transport) instead of making more and
more parameters?

[guoweis_left_chromium, 2015/08/26 14:43:40]

origin is used for completely different things. I don't think it should be put
together. I could put enable_multiple_routes and enable_udp_transport together
if that looks better.

[pthatcher2, 2015/08/26 18:25:39]

Yeah, that would be nice.  Why not just use P2PPortAllocator::Config.

       : socket_dispatcher_(socket_dispatcher),
         network_manager_(network_manager),
         socket_factory_(socket_factory),
         origin_(origin),
-        enable_multiple_routes_(enable_multiple_routes) {}
+        enable_multiple_routes_(enable_multiple_routes),
+        enable_udp_transport_(enable_udp_transport) {}

[pthatcher2, 2015/08/25 23:12:34]

Even if we make the Chrome flag "ForceThroughProxy", I think we can keep this
one as "disable_udp_transport".

 
   cricket::PortAllocator* CreatePortAllocator(
       const std::vector<StunConfiguration>& stun_servers,
@@ -149,6 +151,7 @@ class P2PPortAllocatorFactory : public webrtc::PortAllocatorFactoryInterface {
       config.relays.push_back(relay_config);
     }
     config.enable_multiple_routes = enable_multiple_routes_;
+    config.disable_udp_transport = !enable_udp_transport_;

[pthatcher2, 2015/08/25 23:12:34]

Can we keep it consistent across both (either enable on both or disable on
both)?  I'd prefer "disable".

[guoweis_left_chromium, 2015/08/26 14:43:40]

I also like disable more but if we looked at the old code review on
"enable_multiple_routes", it was a CL feedback to change it from disable to
enable. For consistency, I'll keep everything to be enable_udp_transport.

 
     return new P2PPortAllocator(
         socket_dispatcher_.get(), network_manager_,
@@ -170,6 +173,8 @@ class P2PPortAllocatorFactory : public webrtc::PortAllocatorFactoryInterface {
   // When false, only 'any' address (all 0s) will be bound for address
   // discovery.
   bool enable_multiple_routes_;
+
+  bool enable_udp_transport_;
 };
 
 PeerConnectionDependencyFactory::PeerConnectionDependencyFactory(
@@ -406,19 +411,22 @@ PeerConnectionDependencyFactory::CreatePeerConnection(
   if (!GetPcFactory().get())
     return NULL;
 
-  // Copy the flag from Preference associated with this WebFrame.
-  bool enable_multiple_routes = true;
   rtc::scoped_ptr<PeerConnectionIdentityStore> identity_store(
       new PeerConnectionIdentityStore(
           GURL(web_frame->document().url()),
           GURL(web_frame->document().firstPartyForCookies())));
 
+  // Copy the flag from Preference associated with this WebFrame.
+  bool enable_multiple_routes = true;
+  bool enable_udp_transport = false;
   if (web_frame && web_frame->view()) {
     RenderViewImpl* renderer_view_impl =
         RenderViewImpl::FromWebView(web_frame->view());
     if (renderer_view_impl) {
       enable_multiple_routes = renderer_view_impl->renderer_preferences()
                                     .enable_webrtc_multiple_routes;
+      enable_udp_transport = renderer_view_impl->renderer_preferences()
+                                 .enable_webrtc_udp_transport;
     }
   }
 
@@ -426,7 +434,7 @@ PeerConnectionDependencyFactory::CreatePeerConnection(
       new rtc::RefCountedObject<P2PPortAllocatorFactory>(
           p2p_socket_dispatcher_.get(), network_manager_, socket_factory_.get(),
           GURL(web_frame->document().url().spec()).GetOrigin(),
-          enable_multiple_routes);
+          enable_multiple_routes, enable_udp_transport);
 
   return GetPcFactory()->CreatePeerConnection(config,
                                               constraints,