Description of problem:
Follow-up on bug 1324592.
If the 'Recently opened/edited' records contain files from a deleted/nonexistent repository, the corresponding panels in the UI will fail to load.

Version-Release number of selected component (if applicable):
BxMS 6.3.0 CR1

Steps to Reproduce:
1. Create a repository with a project and a DRL inside.
2. Open the DRL.
3. Open the Explore -> Recently opened panel. You will see the DRL listed there.
4. Go to Administration and delete the repository.
5. Return to Authoring and reopen the Explore -> Recently opened panel.

Actual results:
The loading animation (three squares) stays present, no data is loaded. The js console of the browser shows an exception (see screenshot).

Expected results:
The data finishes loading and you can see the DRL listed as previously.