Clean up the Repository unit tests.
Review Request #11139 — Created Aug. 17, 2020 and submitted
The Repository unit tests are pretty old, and predated the modern spying
capabilities we enjoy today. They instead overrode much functionality,
and had crude ways of testing results. If anything were to break, these
could impact future unit tests.
This change is a small cleanup that moves over to using spies instead.
There's a few other small cleanups included, helping make these tests
more readable and maintainable going forward.
Unit tests pass.