rebalance stuck when persistence was stopped(certain test steps)

steps from http://review.couchbase.org/#/c/23174/
rebalance.rebalanceinout.RebalanceInOutTests.rebalance_in_out_at_once_persistence_stopped,items=1000,num_nodes_with_stopped_persistence=3,num_items_without_persistence=1000,sasl_buckets=1,standard_buckets=1,nodes_init=3,nodes_in=2,nodes_out=1

1. 3 node in cluster, 3 different buckets with 1000 items
2. stop persistence on all nodes for all buckets
3. update 50% items and add new 50% items
4. 2 nodes in, 1 out and start rebalance

result: rebalance hangs with "progress":0.0

execution logs are attached