WebHdfs does not work if HA is enabled on NN but logical URI is not configured.

After HDFS-6100, namenode unconditionally puts the logical name (name service id) as the token service when redirecting webhdfs requests to datanodes, if it detects HA.

For HA configurations with no client-side failover proxy provider (e.g. IP failover), webhdfs does not work since the clients do not use logical name.