BUG-1555: skip choices which are not valid in a particular context

We are enumerating the use of a case in all the possible contexts, which
may partially fail. Instead of failing completely, just skip the
offending case.

Change-Id: Icbf137266784e0f469a258b2bb312db4e01bd8f6
Signed-off-by: Robert Varga <rovarga@cisco.com>
Merge "BUG-1555: skip choices which are not valid in a particular context"