index.js
function trackEnd(event, properties) {
  RNSensorsAnalytics && RNSensorsAnalytics.trackEnd && RNSensorsAnalytics.trackEnd(event, properties);
}
function trackEnd(event, properties) {
  RNSensorsAnalytics && RNSensorsAnalytics.trackEnd && RNSensorsAnalytics.trackEnd(event, properties);
}
事件结束

@param event
@param properties