[xwiki-devs] [Proposal] Add support for referencing easily XObjects in the model module

Hi devs, ATM in the model module there's no ability to reference an xobject other than by using a free form name. The problem is that this is not really usable. This is why we introduced the BaseObjectProperty in oldcore. However this is major PITA since we can't have clean code that create an object reference and that doesn't depend on oldcore. I'd like to propose the following: * Modify ObjectProperty to add 2 named parameters: Class reference and position * Make the name optional in EntityReference This means that when we use an EntityReferenceResolver to resolve "wiki:space.page^wiki2:space2.page2" we get an ObjetReference with: * name = null * param1: name = "classReference", value = EntityReference * param2: name = "objectPosition", value = 0 Rationale: * This is exactly what we already do for Locale (and what we'll do for Version too probably) so it's logical to do it for Object References too Consequences: * We need to modify the Seralizers/Resolvers accordingly * We need to modify EntityReference to support a null name * We deprecate BaseObjectProperty * Probably some other stuff to modify like modifying event listeners listening on objects since it's now going to be much easier, etc WDYT? Thanks -Vincent