Make sure we set init the storage before trying to get the cache

without the init the following could happen if there had been no access
to the storage yet.

1. Call getCache
2. Since the storage is not init yet, $this->cache and $this->storage
are not set yet
3. Construct a new \OCA\Files_Sharing\Cache
  i. This calls $this->getSourceRootInfo()
  ii. This then calls init
  iii. Init fails and sets storage to FailedStorage and cache to
  FailedCache
4. We set cache to the newly constructed \OCA\Files_Sharing\Cache
  * It should just be a FailedCache

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>

Author: rullzer

apps/files_sharing/lib/SharedStorage.php

@@ -40,6 +40,7 @@
 use OCP\Files\Cache\ICacheEntry;
 use OCP\Files\NotFoundException;
 use OCP\Files\Storage\IStorage;
+use OCP\Files\StorageNotAvailableException;
 use OCP\Lock\ILockingProvider;
 use OC\User\NoUserException;
 
@@ -114,6 +115,7 @@ private function init() {
 			return;
 		}
 		$this->initialized = true;
+
 		try {
 			Filesystem::initMountPoints($this->superShare->getShareOwner());
 			$sourcePath = $this->ownerView->getPath($this->superShare->getNodeId());
@@ -357,6 +359,8 @@ public function getItemType() {
 	 * @return Cache
 	 */
 	public function getCache($path = '', $storage = null) {
+		$this->init();
+
 		if ($this->cache) {
 			return $this->cache;
 		}