Move the concept of multiple route into Network

webrtc/base/network.cc

Index: webrtc/base/network.cc
diff --git a/webrtc/base/network.cc b/webrtc/base/network.cc
index 8dda89f42c08dc190ddc5b2f21d3cf16d9fabd3d..ff9c01afdfa2e2b63e49ddc0b532e5050f4be9e2 100644
--- a/webrtc/base/network.cc
+++ b/webrtc/base/network.cc
@@ -163,6 +163,11 @@ NetworkManager::NetworkManager() {
 NetworkManager::~NetworkManager() {
 }
 
+NetworkManager::EnumerationPermission NetworkManager::enumeration_permission()
+    const {
+  return kEnumerationAllowed;
+}
+
 NetworkManagerBase::NetworkManagerBase()
     : enumeration_permission_(NetworkManager::kEnumerationAllowed),
       max_ipv6_networks_(kMaxIPv6Networks),