// Update labeled object.
		if labelsKey == l.labelsKey {
			// No change to labels.
			return
		}
		// Delete before readding.
		m.delete(key)
	}
	// Add labeled object.
	labels = copyLabels(labels)
	labeledObject := &labeledObject{
		key:       key,
		labels:    labels,
		labelsKey: labelsKey,
	}
	m.labeledObjects[key] = labeledObject
	// Add associations.