mark path as checked

lib/private/files/cache/watcher.php

@@ -119,6 +119,7 @@ class Watcher {
 	 */
 	public function needsUpdate($path, $cachedData) {
 		if ($this->watchPolicy === self::CHECK_ALWAYS or ($this->watchPolicy === self::CHECK_ONCE and array_search($path, $this->checkedPaths) === false)) {
+			$this->checkedPaths[] = $path;
 			return $this->storage->hasUpdated($path, $cachedData['storage_mtime']);
 		}
 		return false;