Fix build break on win32

Change-Id: I3b317e6d6a0d6123e73067d88aba194c54ed00bf
Reviewed-on: http://review.couchbase.org/24988
Reviewed-by: Sergey Avseyev <sergey.avseyev@gmail.com>
Tested-by: Sergey Avseyev <sergey.avseyev@gmail.com>