This method was never invoked and its logic moved to `setBeanFactory` as it is in the other 'processing' strategies.
Comes to mind an idea to introduce `IntegrationConversionServiceAware`, implement it in the 'AbstractExpressionEvaluator', eliminate similar code everywhere, and in the potential `setIntegrationConversionService` make a check if the `conversionService` wasn't setted before manually.