Eliminate creating a new broker ingress span and add broker ingress a…

…ttributes to the existing http span (#1585)

* Eliminate broker ingress span

* Set broker ingress span name

* Fix TestGCPBrokerTracing integration test

pkg/broker/ingress/handler.go

@@ -134,8 +134,8 @@ func (h *Handler) ServeHTTP(response nethttp.ResponseWriter, request *nethttp.Re
 
 	event.SetExtension(EventArrivalTime, cev2.Timestamp{Time: time.Now()})
 
-	ctx, span := trace.StartSpan(ctx, kntracing.BrokerMessagingDestination(broker))
-	defer span.End()
+	span := trace.FromContext(ctx)
+	span.SetName(kntracing.BrokerMessagingDestination(broker))
 	if span.IsRecordingEvents() {
 		span.AddAttributes(
 			append(

test/e2e/lib/helpers/broker_tracing.go

@@ -242,8 +242,9 @@ func BrokerTestTree(namespace string, brokerName string, trigger string, respTri
 
 func ingressSpan(namespace string, broker string) *SpanMatcher {
 	brokerName := fmt.Sprintf("broker:%s.%s", broker, namespace)
+	spanName := fmt.Sprintf("Recv.%s", brokerName)
 	return &SpanMatcher{
-		Name: brokerName,
+		Name: spanName,
 		Labels: map[string]string{
 			"messaging.system":      "knative",
 			"messaging.destination": brokerName,