This is to test if the user list and paths are correct, even when a
recipient renamed the received shared folder

Switch to new javascript mimetype resolver

* introduced with #17159

In some corner cases, an outgoing share exists but sharing is not
allowed for the current user. This would cause the file list to break
because the static text could not be rendered as the owner was
undefined.

While making the AppStore ready for 8.1 I also deleted some dummy entries which means that these IDs do not resolve anymore. We should remove them to prevent errors such as https://github.com/owncloud/core/issues/17307

Ref https://github.com/owncloud/activity/issues/320#issuecomment-117691867

Most of the time it doesn't make sense to forward Guzzle's
RequestException, so we convert it to StorageNotAvailable instead.

This prevents unpredictable error codes to block access to unrelated
folders needlessly.