Tells the delegate that indexing is being throttled.
- iOS 9.0+
- macOS 10.13+
- Mac Catalyst 13.0+
- Core Spotlight
The indexing that’s being throttled.
In some situations, such as when the device is using battery only, the system may throttle indexing to save power. You can implement this method to be notified of this situation so that you can respond by, for example, prioritizing the items to index.