I don't know why it hangs, but seems even without closing, the test
still fails after reverting fc9080a0
(fdo#67685 open xSourceLibrariesStor only when needed, 2013-08-02).

Once the test no longer hangs, of course feel free to add this back.

Change-Id: If124b7f57a8fa2d522ebdb448366aec6f1ff4987