NIMChatroomNotificationContent 成员列表

成员的完整列表，这些成员属于 NIMChatroomNotificationContent,包括所有继承而来的类成员

	eventType	NIMChatroomNotificationContent
	ext	NIMChatroomNotificationContent
-	notificationType	NIMNotificationContent
	notifyExt	NIMChatroomNotificationContent
	revokedMessageId	NIMChatroomNotificationContent
	revokedMessageTime	NIMChatroomNotificationContent
	source	NIMChatroomNotificationContent
	tags	NIMChatroomNotificationContent
	targets	NIMChatroomNotificationContent