Merge pull request #24459 from fgrzadkowski/unschedulable_pod

Automatic merge from submit-queue

Add pod condition PodScheduled to detect situation when scheduler tried to schedule a Pod, but failed

Set `PodSchedule` condition to `ConditionFalse` in `scheduleOne()` if scheduling failed and to `ConditionTrue` in `/bind` subresource.

Ref #24404

@mml (as it seems to be related to "why pending" effort)

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pkg/api/types.go

@@ -1071,6 +1071,8 @@ type PodConditionType string
 
 // These are valid conditions of pod.
 const (
+	// PodScheduled represents status of the scheduling process for this pod.
+	PodScheduled PodConditionType = "PodScheduled"
 	// PodReady means the pod is able to service requests and should be added to the
 	// load balancing pools of all matching services.
 	PodReady PodConditionType = "Ready"