Some minor fixes:

 1) Change setCachedCapturingScopeInfo to use LambdaScopeInfo - so we don't have to keep doing those casts back and forth
 2) Fix NestedConditionalTransformer to use pointer version of getDeducedTemplateArguments() (should have been updated with the prior patch)
 3) Add a query function within LocalInstantiationScope: 'hasInstantiationOf' that does NOT assert if the instantiated decl is not found - this might need to be removed later - but it might have a use during nested variadic captures