The possibility existed that an activity was set to a task that it was
already being set to. If that were to happen, and it was the only
activity in the only task of the stack the stack would be deleted.
This fixes that situation and logs it as well to confirm that it does
fix bug 11272935. Logging to be deleted upon successful monkey run
exhibiting the log.
Change-Id: I436fdcc9a3734adad81d3ef90f29b93b3ac4dfcd
19d9bd54d3