[XDCR] Replication to ElasticSearch 1.7 doesn't work in Spock

Steps to reproduce:
1. create xdcr remote cluster pointing to ES server
2. start replication
==>
Replication fails with : Failed to connect to cluster reference remoteCluster/6gEjIZbREnqTkfWang8cJYTOtDZScE0vPwVdYlPm9qk=

The replication to ES works fine in 4.5 GA

It seems like xdcr now calls the <remote cluster>/pools/nodes api which fails in case of ES.

4.5 log:
ReplicationSpecService 2016-11-16T15:58:01.862-08:00 [INFO] Start ValidateAddReplicationSpec, sourceBucket=bucket-1, targetCluster=Elastic, targetBucket=perf_elastic_index
ReplicationSpecService 2016-11-16T15:58:01.887-08:00 [INFO] Result from local bucket look up: err_source=<nil>, time taken=24.846301ms
ReplicationSpecService 2016-11-16T15:58:01.895-08:00 [INFO] Successfully retrieved target cluster reference. time take=8.278156ms

Spock log:
ReplicationSpecService 2016-11-16T15:40:13.776-08:00 [INFO] Start ValidateAddReplicationSpec, sourceBucket=bucket-1, targetCluster=Elastic, targetBucket=perf_elastic_index
ReplicationSpecService 2016-11-16T15:40:13.802-08:00 [INFO] Result from local bucket look up: err_source=<nil>, time taken=25.922461ms
RemoteClusterService 2016-11-16T15:40:13.803-08:00 [INFO] Remote cluster reference remoteCluster/6gEjIZbREnqTkfWang8cJYTOtDZScE0vPwVdYlPm9qk= has a bad connectivity, didn't populate alternative connection strings. err=Failed on calling host=172.23.99.211:9091, path=/pools/nodes, err=<nil>, statusCode=404
RemoteClusterService 2016-11-16T15:40:13.803-08:00 [INFO] nodes_connStrs from old cache =[]
RemoteClusterService 2016-11-16T15:40:13.803-08:00 [INFO] Connstr 172.23.99.211:9091 in remote cluster reference failed to connect. Try to use alternative connStr
AdminPort 2016-11-16T15:40:13.803-08:00 [ERROR] Error creating replication. errorsMap=map[toCluster:cannot find remote cluster
err = Failed to connect to cluster reference remoteCluster/6gEjIZbREnqTkfWang8cJYTOtDZScE0vPwVdYlPm9qk=
]
AdminPort 2016-11-16T15:40:13.803-08:00 [INFO] Finished doCreateReplicationRequest call

Logs attached.