function hasChanges(mPropertyBag) {
		mPropertyBag.includeCtrlVariants = true;
		return PersistenceWriteAPI._getUIChanges(mPropertyBag)
		.then(function(aChanges) {
			return aChanges.length > 0;
		});
	}
Checks if changes exist for the flex persistence associated with the selector control;

@param {object} mPropertyBag Object with parameters as properties
@param {sap.ui.fl.Selector} mPropertyBag.selector To retrieve the associated flex persistence
@returns {Promise<boolean>} Promise that resolves to a boolean indicating if changes exist