OnPerformanceAlarmsType typedef Null safety

OnPerformanceAlarmsType = void Function(PerformanceAlarmMode mode, String roomId, PerformanceAlarmReason reason, SourceWantedData data)

mode：指示本地是否开启发布回退功能

roomId：未开启发布性能回退时，roomId 为空；开启发布性能回退时，roomId 是告警影响的房间 ID

reason：告警原因

data：性能回退相关数据

Implementation

typedef OnPerformanceAlarmsType = void Function(PerformanceAlarmMode mode,
    String roomId, PerformanceAlarmReason reason, SourceWantedData data);