internal ConnectionPoint(ConnectionPointContainer container, IEventSource <SinkType> source)
 {
     this.container  = container ?? throw new ArgumentNullException(nameof(container));
     this.source     = source ?? throw new ArgumentNullException(nameof(source));
     this.sinks      = new Dictionary <uint, SinkType>();
     this.nextCookie = 1;
 }
 internal ConnectionPoint(ConnectionPointContainer container, IEventSource <SinkType> source)
 {
     if (null == container)
     {
         throw new ArgumentNullException("container");
     }
     if (null == source)
     {
         throw new ArgumentNullException("source");
     }
     this.container = container;
     this.source    = source;
     sinks          = new Dictionary <uint, SinkType>();
     nextCookie     = 1;
 }