Create a new preference which disables UDP protocol for WebRTC

chrome/common/pref_names.cc

Index: chrome/common/pref_names.cc
diff --git a/chrome/common/pref_names.cc b/chrome/common/pref_names.cc
index 9d21f958f0fa622a09711e80b9d3baea6b95d84c..b49dcc9ad71d5c3bcc6fddc203f75af1385ec8ac 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -1193,10 +1193,15 @@ const char kToolbarIconSurfacingBubbleLastShowTime[] =
     "toolbar_icon_surfacing_bubble_show_time";
 #endif
 
+#if defined(ENABLE_WEBRTC)
 // Whether WebRTC should bind to individual NICs to explore all possible routing
 // options. Default is true.
-#if defined(ENABLE_WEBRTC)
 const char kWebRTCMultipleRoutesEnabled[] = "webrtc.multiple_routes_enabled";
+// Whether WebRTC can use nonproxied UDP to connect. When this is true, WebRTC
+// will use UDP transport which doesn't use proxy and might leak IP addresses
+// when no UDP-supporting proxy is configured. Default is true.
+const char kWebRTCNonProxiedUdpTransportEnabled[] =

[pthatcher2, 2015/08/26 21:09:59]

Might be more clear as "Whether WebRTC should use non-proxied UDP. If false,
WebRTC will not send UDP unless it goes through a proxy.  If no UDP proxy is
configured, it will not send UDP.  If true, WebRTC will send UDP regardless of
whether or not a proxy is configured."

+    "webrtc.nonproxied_udp_transport_enabled";
 #endif
 
 // *************** LOCAL STATE ***************