Note fluid is a failsafe mode aware extensions since its used in the install tool. We thus need a ServiceProvider.php to correctly instantiate / inject these class objects. This would be simple, but ViewHelperResolver has state, and the failsafe mode expects injected services to not have state.

So, to retrieve a ViewHelperResolver instance, an instance of this factory is retrieved instead (which is a singleton), which then creates a 'fresh' instance of the ViewHelperResolver each time create() is called.