COMP: Fix GCC warning about unused typedef in ConceptChecking

New in GCC 4.8 is a warning about when a local typedef is not
used. The most frequent offender of this incidental warning is the
concept checking used. This patch uses an approach suggested by Brad
King which uses the type as a template argument, to an instantiated
empty class.

Change-Id: Icc2c89e377639f829e0c1fbed4468c92eae813d5
Merge topic 'FixUnUsedTypedefInConceptChecking'

8329f687 COMP: Fix GCC warning about unused typedef in ConceptChecking