The code from two years back had to be upgraded to E4, and now a bunch of stuff does not work anymore. One of these is the IEvaluationService if used like this:
IEvaluationService
eventBroker.post(UIEvents.REQUEST_ENABLEMENT_UPDATE_TOPIC, UIEvents.ALL_ELEMENT_ID);
See also Eclipse bug 436755 and Eclipse Wiki: Eclipse 4 - RCP - Event Model