Revert "Sort by top-most path in getIncomplete()"

This reverts commit 71c78a0.

lib/private/Files/Cache/Cache.php

@@ -3,7 +3,6 @@
  * @copyright Copyright (c) 2016, ownCloud, Inc.
  *
  * @author Andreas Fischer <bantu@owncloud.com>
- * @author Ari Selseng <ari@selseng.net>
  * @author Artem Kochnev <MrJeos@gmail.com>
  * @author Björn Schießle <bjoern@schiessle.org>
  * @author Florin Peter <github@florin-peter.de>
@@ -846,14 +845,15 @@ public function getAll() {
 	/**
 	 * find a folder in the cache which has not been fully scanned
 	 *
-	 * If multiple incomplete folders are in the cache, the top-most folder will be returned
-	 * This avoids a weird edge case when multiple incomplete folders do not get scanned properly
+	 * If multiple incomplete folders are in the cache, the one with the highest id will be returned,
+	 * use the one with the highest id gives the best result with the background scanner, since that is most
+	 * likely the folder where we stopped scanning previously
 	 *
 	 * @return string|bool the path of the folder or false when no folder matched
 	 */
 	public function getIncomplete() {
 		$query = $this->connection->prepare('SELECT `path` FROM `*PREFIX*filecache`'
-			. ' WHERE `storage` = ? AND `size` = -1 ORDER BY `path` ASC', 1);
+			. ' WHERE `storage` = ? AND `size` = -1 ORDER BY `fileid` DESC', 1);
 		$query->execute([$this->getNumericStorageId()]);
 		if ($row = $query->fetch()) {
 			return $row['path'];