Work around different versions of patch(1) in unit tests
Review Request #10164 — Created Sept. 22, 2018 and submitted
We had a unit test that depended on the specific version of
installed. Newer versions of patch will accept a diff that contains no
hunks, whereas older versions will fail with a message saying that the
input contained only garbage.
We now have unit tests that check the correct behaviour happens in both
cases by replacing our call to
Ran unit tests.