Comment 1 for bug 1479579

Reviewed: https://review.openstack.org/206974
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=b101190f3261535daf5848a5a77e8902f3a7a4a1
Submitter: Jenkins
Branch: master

commit b101190f3261535daf5848a5a77e8902f3a7a4a1
Author: huangtianhua <email address hidden>
Date: Wed Jul 29 14:25:22 2015 +0800

    Don't raise exception when get nested stack

    1. Stack.load() won't return None, instead will raise
    notFound exception if we can't get the stack from db.
    So we should catch the notFound exception in
    StackResource.nested() when loading.
    2. Return None if we catch the notFound when get the
    nested, due there are many places where we call the
    nested(), and raise the notFound exception makes no sense.

    Closes-Bug: #1479579
    Change-Id: I2540ca13572dfe628e6fc596815bee427b41290f