Fix SortIpAddressList to iterate properly.

SortIpAddressList was using strtok improperly.

Bug: 10458541
Change-Id: Idf755c39473e9b85b83bf118e9aa5a63c6a39338
diff --git a/src/proxy_resolver_v8.cc b/src/proxy_resolver_v8.cc
index ee0510b..dc09d80 100644
--- a/src/proxy_resolver_v8.cc
+++ b/src/proxy_resolver_v8.cc
@@ -300,7 +300,7 @@
     if (!ParseIPLiteralToNumber(tok_list, &ip_num))
       return false;
     ip_vector.push_back(IPAddress(tok_list, ip_num));
-    tok_list = strtok(tok_list, ";");
+    tok_list = strtok(NULL, ";");
   }
 
   if (ip_vector.empty())  // Can happen if we have something like