成员的完整列表，这些成员属于 com.netease.nimlib.sdk.v2.statistics.V2NIMStatisticsService,包括所有继承而来的类成员

addStatisticsListener(V2NIMStatisticsListener listener)	com.netease.nimlib.sdk.v2.statistics.V2NIMStatisticsService
getDatabaseInfos(V2NIMSuccessCallback< List< V2NIMDatabaseInfo >> success, V2NIMFailureCallback failure)	com.netease.nimlib.sdk.v2.statistics.V2NIMStatisticsService
removeStatisticsListener(V2NIMStatisticsListener listener)	com.netease.nimlib.sdk.v2.statistics.V2NIMStatisticsService