Stack preview does not pass files to nested stacks

[Zane Bitter]

While looking at the fix for bug 1351005, I noticed that when doing a stack preview, the files are not added to the template of nested stacks as they are when creating or updating a nested stack. That seems wrong, but if I am crazy just close this bug as Invalid.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/114673

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/114673
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=1ee74eb8928718cb21c835a27c7d8510bf63a000
Submitter: Jenkins
Branch: master

commit 1ee74eb8928718cb21c835a27c7d8510bf63a000
Author: Anderson Mesquita <email address hidden>
Date: Fri Aug 15 17:30:45 2014 -0400

    Refactor nested stack create/update/preview

    The bug #1357433 was caused by the fact that stack parsing for a stack
    resource on create/update/preview is pretty similar but repeated in all
    three places. This refactors them to move common logic to a single
    place, making sure all validation in consistent and all params are
    passed in the same way.

    Closes-Bug: #1357433
    Change-Id: I20ee7f9a6dbf047798b0cc954aa861f774e683b9