Fix non-deterministic a-a test

You can find more details in the bug 1283020 description.

It should fix failures on the following CRs:

* I7b677a74196b20c44498b33ec321f30ae96148da
* I5a637632e0a7ad437e05cea40b25b75e73fd8497

Change-Id: I96483346578e3b9891e138546cf8c9bafdc15ede
Closes-Bug: #1283020
Expand swift data source credential tests

Added two tests that should trigger exceptions -
 0. credentials w/ password missing user
 1. credentials w/ user missing password

Change-Id: I5a637632e0a7ad437e05cea40b25b75e73fd8497
Merge "Fix non-deterministic a-a test"
Merge "Expand swift data source credential tests"