LogSyncerThread not getting shutdown waiting for the interrupted flag

In the LogSyncer run() we keep looping till this.isInterrupted flag is set.

But in some cases the DFSclient is consuming the Interrupted exception. So
we are running into infinite loop in some shutdown cases.

I would suggest that as we are the ones who tries to close down the
LogSyncerThread we can introduce a variable like

Close or shutdown and based on the state of this flag along with
isInterrupted() we can make the thread stop.