code: function _proxyDeprecatedEvent(eventName) {
              DeprecationWarning.deprecateEvent(exports,
                                                MainViewManager,
                                                eventName,
                                                eventName,
                                                "DocumentManager." + eventName,
                                                "MainViewManager." + eventName);
          }
docs: Listens for the given event on MainViewManager, and triggers a copy of the event on DocumentManager whenever it occurs