// Cancellation/timeouts are removed, so parent cancellations/timeout will
// not propagate from parent.
// Context values are preserved.
// This can be used for goroutines that live beyond the parent context.
func bgContext(parent context.Context) context.Context {
	return bgCtx{parent: parent}
}

type bgCtx struct {
	parent context.Context
}

func (a bgCtx) Done() <-chan struct{} {