isImplicitInitializerAllowed

C++ uses implicit constructor calls for statements like A a; but this only applies to types that are actually classes and not just primitive types or typedef aliases of primitives. Thus, during AST construction, we can only suggest that an implicit constructor call might be allowed by the language (so this is set to true for C++ but false for Java, as such a statement in Java leads to an uninitialized variable). The final decision can then be made after we have analyzed all classes present in the current scope.