Use more specific assertions for 'in' checks.

Review Request #6064 — Created July 4, 2014 and submitted — Latest diff uploaded

Information

Review Board
release-2.0.x
3797c0d...

Reviewers

A lot of old code used assertTrue(blah in blah), or variants on that,
which didn't tell you much if there was a failure. Nowadays, we have
assertIn and assertNotIn, which we can use instead. This switches our
tests to use these.

Unit tests pass.