If backup cannot be found while resetting its status, Cinder
exception (BackupNotFound) is raised instead of HTTP exception.
This patch handles the BackupNotFound exception and raises
HTTPNotFound exception.
APIImpact
HTTPNotFound exception (404) is raised instead of BackupNotFound
if backup cannot be found during backup reset-status.
Change-Id: I5a41c71a83c05d09c6d1e2e506adca6cfbe3e890
Closes-Bug: #1474748
b5e84020ae