Have Activator key off of Active not Ready. (#2395)

This adjusts the condition that the activator keys off of to determine whether it can start forwarding requests to the Revision.  In the current world, this change is just splitting hairs because these conditions end up being largely the same; however, this is relevant cleanup if we want to shift to a world where `Active=False` does not trigger `Ready=False` because requests to the activator would incorrectly see an `IsReady()` Revision and incorrectly forward traffic.

Peripherally related to: #2394

pkg/activator/revision.go

@@ -78,8 +78,8 @@ func (r *revisionActivator) activateRevision(namespace, name string) (*v1alpha1.
 	serviceName, configurationName := getServiceAndConfigurationLabels(revision)
 	r.reporter.ReportRequest(namespace, serviceName, configurationName, name, 1.0)
 
-	// Wait for the revision to be ready
-	if !revision.Status.IsReady() {
+	// Wait for the revision to not require activation.
+	if revision.Status.IsActivationRequired() {
 		wi, err := r.knaClient.ServingV1alpha1().Revisions(rev.namespace).Watch(metav1.ListOptions{
 			FieldSelector: fmt.Sprintf("metadata.name=%s", rev.name),
 		})
@@ -88,24 +88,24 @@ func (r *revisionActivator) activateRevision(namespace, name string) (*v1alpha1.
 		}
 		defer wi.Stop()
 		ch := wi.ResultChan()
-	RevisionReady:
+	RevisionActive:
 		for {
 			select {
 			case <-time.After(r.readyTimout):
 				// last chance to check
-				if revision.Status.IsReady() {
-					break RevisionReady
+				if !revision.Status.IsActivationRequired() {
+					break RevisionActive
 				}
 				return nil, errors.New("Timeout waiting for revision to become ready")
 			case event := <-ch:
 				if revision, ok := event.Object.(*v1alpha1.Revision); ok {
-					if !revision.Status.IsReady() {
+					if revision.Status.IsActivationRequired() {
 						logger.Info("Revision is not yet ready")
 						continue
 					} else {
 						logger.Info("Revision is ready")
 					}
-					break RevisionReady
+					break RevisionActive
 				} else {
 					return nil, fmt.Errorf("Unexpected result type for revision: %v", event)
 				}

pkg/activator/revision_test.go

@@ -210,8 +210,9 @@ func (b *revisionBuilder) withReady(ready bool) *revisionBuilder {
 	if ready {
 		b.revision.Status.MarkContainerHealthy()
 		b.revision.Status.MarkResourcesAvailable()
+		b.revision.Status.MarkActive()
 	} else {
-		b.revision.Status.MarkContainerMissing("reasonz")
+		b.revision.Status.MarkInactive("reasonz", "detailz")
 	}
 	return b
 }