Notify network observers of route changes.

This reverts commit 20d3f5e856a38ef22851e32d7f9b6a7cd02eb459.

Bug: 9180552
Change-Id: I004448e2f0c731f6ca2c6d3535dc4dd51a622293
diff --git a/server/ResponseCode.h b/server/ResponseCode.h
index d8fafbb..054939d 100644
--- a/server/ResponseCode.h
+++ b/server/ResponseCode.h
@@ -77,5 +77,6 @@
     static const int InterfaceClassActivity         = 613;
     static const int InterfaceAddressChange         = 614;
     static const int InterfaceDnsInfo               = 615;
+    static const int RouteChange                    = 616;
 };
 #endif