Add policy to control valid UDP port range in 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 3e68105a544fbe582117ef14c96542870d7fc074..222084515a4f4cd1c91b466a5683548faa6bfe16 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -1275,6 +1275,8 @@ const char kWebRTCNonProxiedUdpEnabled[] =
 // Define the IP handling policy override that WebRTC should follow. When not
 // set, it defaults to "default".
 const char kWebRTCIPHandlingPolicy[] = "webrtc.ip_handling_policy";
+// Define range of UDP ports allowed to be used by WebRTC PeerConnections.
+const char kWebRTCUDPPortRange[] = "webrtc.udp_port_range";
 #endif
 
 // *************** LOCAL STATE ***************