Before, when recheck_account_existence or recheck_container_existence
was set to zero, get_info requests for accounts or containers wouldn't
populate the env cache for the current request, so it wouldn't return
the data *it just got*.
Now, we'll still populate the env cache and memcache, as a cache time of
zero means "keep it indefinitely". See the memcache docs at
https://github.com/memcached/memcached/blob/1.4.25/doc/protocol.txt#L163
Change-Id: Ia648263073bc88e35216cafb76821b7ce02c1d03
Closes-Bug: 1224734