src/vs/platform/storage/electron-main/storageIpc.ts/StorageDatabaseChannel/serializeStorageChangeEvents
class StorageDatabaseChannel:	private serializeStorageChangeEvents(events: IStorageChangeEvent[], storage: IStorageMain): ISerializableItemsChangeEvent {
		const changed = new Map<Key, Value>();
		const deleted = new Set<Key>();
		events.forEach(event => {
			const existing = storage.get(event.key);
			if (typeof existing === 'string') {
				changed.set(event.key, existing);
			} else {
				deleted.add(event.key);
			}
		});

		return {
			changed: Array.from(changed.entries()),
			deleted: Array.from(deleted.values())
		};
	}