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