_updateStartedHandler(oEvent) {
			if (oEvent.getParameter && oEvent.getParameter("reason") === "Growing") {
				return this._appendDataFromBackend();
			}
			return Promise.resolve();
		}
Proxy handler that is called if <code>updateStarted</code> events are fired.
Delegates to <code>_appendDataFromBackend</code> in case of a <code>Growing</code> event.
<code>Growing</code> events are triggered if the user clicks on <code>More</code> or scrolls down in the <code>Select Contexts</code> list.
@param {sap.ui.base.Event} oEvent - Event object
@returns {Promise} Resolves with additional data