Wrong action in XWikiContext for extensions contributing a new entity action URL handler

If an extension implements ResourceReferenceHandler<EntityResourceAction> then its action is not correctly set in the XWikiContext.

The reason is that because the action is set early in XWikiRequestProcessor#processPath() and before any XWikiContext is created and thus the DefaultEntityResourceActionLister which uses the ContextComponentManagerProvider fails to find the contributed component (since the context is null it looks only in the root CM).