Pass route add/delete errors back to CommandListener.

Change-Id: Id1d6d578963080e141f71bc1303801fc53bce40a
diff --git a/server/NetworkController.h b/server/NetworkController.h
index 30c9142..4e93fa1 100644
--- a/server/NetworkController.h
+++ b/server/NetworkController.h
@@ -67,10 +67,10 @@
 
     // Routes are added to tables determined by the interface, so only |interface| is actually used.
     // |netId| is given only to sanity check that the interface has the correct netId.
-    bool addRoute(unsigned netId, const char* interface, const char* destination,
-                  const char* nexthop, bool legacy, unsigned uid);
-    bool removeRoute(unsigned netId, const char* interface, const char* destination,
-                     const char* nexthop, bool legacy, unsigned uid);
+    int addRoute(unsigned netId, const char* interface, const char* destination,
+                 const char* nexthop, bool legacy, unsigned uid);
+    int removeRoute(unsigned netId, const char* interface, const char* destination,
+                    const char* nexthop, bool legacy, unsigned uid);
 
     bool isValidNetwork(unsigned netId) const;
 
@@ -79,8 +79,8 @@
     typedef std::multimap<unsigned, std::string>::iterator InterfaceIterator;
     typedef std::pair<InterfaceIterator, InterfaceIterator> InterfaceRange;
 
-    bool modifyRoute(unsigned netId, const char* interface, const char* destination,
-                     const char* nexthop, bool add, bool legacy, unsigned uid);
+    int modifyRoute(unsigned netId, const char* interface, const char* destination,
+                    const char* nexthop, bool add, bool legacy, unsigned uid);
 
     struct UidEntry {
         int uid_start;