NetInfo V3 support for browser

net/base/network_change_notifier.h

Index: net/base/network_change_notifier.h
diff --git a/net/base/network_change_notifier.h b/net/base/network_change_notifier.h
index 68d0afb4320195b5c5aabaeaa4c4deefd2740f85..4671e4915b0e0de60ca70e031801aa2d3139ae6f 100644
--- a/net/base/network_change_notifier.h
+++ b/net/base/network_change_notifier.h
@@ -35,13 +35,15 @@ class NET_EXPORT NetworkChangeNotifier {
   // Using the terminology of the Network Information API:
   // http://www.w3.org/TR/netinfo-api.
   enum ConnectionType {
-    CONNECTION_UNKNOWN = 0, // A connection exists, but its type is unknown.
+    CONNECTION_UNKNOWN = 0,  // A connection exists, but its type is unknown.
+                             // Also used as a default value.
     CONNECTION_ETHERNET = 1,
     CONNECTION_WIFI = 2,
     CONNECTION_2G = 3,
     CONNECTION_3G = 4,
     CONNECTION_4G = 5,
-    CONNECTION_NONE = 6     // No connection.
+    CONNECTION_NONE = 6,     // No connection.
+    CONNECTION_LAST = CONNECTION_NONE
   };
 
   class NET_EXPORT IPAddressObserver {