Inconsistent use of (Truncated)MiniCartBeanFactory

[selo-ecube]

• MiniCartControllerComponent uses CartInSession to find an existing Cart and MyCartBeanFactory to create an empty Cart if no Cart exists for the session, yet.
• CartInSession uses TruncatedMiniCartBeanFactory to create a truncated MiniCartBean when serializing a Cart into the session cookie.
• The use of MiniCartBeanFactory to create an empty Cart and a TruncatedMiniCartBeanFactory to serialize a non-empty Cart confused me when I was looking for the cause of a bug and makes it harder to introduce a subtype of MiniCartBean. Using TruncatedMiniCartBeanFactory / CartInSession.createMiniCart(...) would require additional null checks in TruncatedMiniCartBeanFactory.