LDDtool: exposed class has a component class with a component exposed class

[rchenatjpl]

If I read CCB-204 correctly, this is a bug, but it's highly possible I read it incorrectly.

I think lddtool should throw an error on the attached, but it doesn't. Super_All_Info has component All_Info which has component Observation_Information, and Super_All_Info and Observation_Information are "exposed" (a term I didn't know about until I saw the error message when I set All_Info's element_flag to true as well).
ccb204lddtoolinputa.xml.gz

[jshughes]

Nice catch and test case. The validate code falsely assumed subclasses had been identified. To fix the problem the algorithm was changed to following "component_of" chain.