Recovered tasks do not move to Bound state

The following events will update the count of allocated containers.

1. release allocation
2. schedule new allocation
3. remove a node

Unfortunately, the event of recovering allocations does not update the count. Hence, the restarted scheduler shows zero value of allocated containers even though there are a bunch of running containers.

This bug cause the restful API of showing container history will return zero, and so the dashboard of WEB UI shows zero also.