Root_on_create per datastore

Reason: Not each datastore has root user entity;

Changes: root_on_create flag per datastore.
fixed test case root_on_create;

Change-Id: I5b2f665cfdb36e9f88d57d04b5e9470085b3362a
Closes-Bug: #1276858
Merge "Root_on_create per datastore"