Kubernetes: Unit Tests for deleteObject NotFound Handling in GC

Problem

The garbage collector's handling of NotFound errors from deleteObject lacked unit test coverage. Edge cases in background and foreground deletion paths weren't verified.

Solution

Added unit tests covering both code paths:

• Default (background propagation): item with dangling owner
• waitingForDependentsDeletion: item whose owner is foreground-deleting

Tests verify that when deleteObject returns NotFound, attemptToDeleteItem enqueues a virtual delete event and returns enqueuedVirtualDeleteEventErr.

Result

Improved test coverage ensures the garbage collector handles externally deleted objects correctly in all scenarios.

Commit: kubernetes/kubernetes@8ed40e7