The WorkingSetMember is transitioned into the OWNED_OBJ state prior to the deletion of the document from the collection.

if (_params.returnDeleted) {
    // Save a copy of the document that is about to get deleted.
    BSONObj deletedDoc = member->obj.value();
    member->obj.setValue(deletedDoc.getOwned());
    member->loc = RecordId();
    member->transitionToOwnedObj();
}

Consider the following sequence of events:

1. The user does {findAndModify: 'coll', query: {}, remove: true}}.
2. The child of the DeleteStage advances and the corresponding WorkingSetMember is in the LOC_AND_OBJ state.
3. We intend to return the delete document, so the WorkingSetMember is transitioned into the OWNED_OBJ state.
4. Collection::deleteDocument() is called and throws a WriteConflictException.
5. The WorkingSetID of the WorkingSetMember is saved in _idRetrying and the DeleteStage returns NEED_YIELD.
6. DeleteStage::work() is called again and status is set to ADVANCED and the id is set to _idRetrying.
7. The WorkingSetMember is in the OWNED_OBJ state and therefore returns false when member->hasLoc() is called.
8. nInvalidateSkips is incremented and the DeleteStage returns NEED_TIME.

Thus, we won't actually retry deleting the document if a WriteConflictException occurred. Instead, we should transition the WorkingSetMember to the OWNED_OBJ state after the delete occurs.