CB-7850 clarify role of whitelist
CB-7712 remove references to closebuttoncaption

The code for this had been previously commented out, but was still listed in
the docs. So remove it from the docs and remove the dead comments.
CB-7876 change test target to avoid undesired redirects

The google.com test target would do automatic redirects to geography-specific
domains depending on where the client is, which leads to different behavior
depending where the tester is. This causes confusion, as the test results
may be different in different geographies. Use a test target that doesn't do
that, so the test results are independent of geography.