src/vs/platform/files/browser/indexedDBFileSystemProvider.ts/IndexedDBFileSystemProvider/deleteKeys
class IndexedDBFileSystemProvider:	private deleteKeys(keys: string[]): Promise<void> {
		return new Promise(async (c, e) => {
			if (keys.length === 0) {
				return c();
			}

			const transaction = this.database.transaction([this.store], 'readwrite');
			transaction.oncomplete = () => c();
			transaction.onerror = () => e(transaction.error);
			const objectStore = transaction.objectStore(this.store);
			for (const key of keys) {
				objectStore.delete(key);
			}
		});
	}