Proper test coverage for Statistics logging

Since removing accesslog (and a number of intermediary, unrelated improvements to the Statistics test suite), I think the qualms raised in the original issue are largely taken care of.

That being said, I think the test coverage is lacking in some places and redundant in others in regards to logging. Specifically:

• Now that node counts are done via AJAX, there's really no distinction between Cache HIT vs. Cache MISS vs. authenticated user. We shouldn't need to test this three times. If the callback works once, it should work all the time, regardless of context.
• Instead, it may be more appropriate to check the existence of the statistics.js file and Drupal settings content that actually performs the data POST for the above three contexts. Currently, there's no test guaranteeing that.

And upon further reflection, checking for the existence of the scripts/settings across cache/uncached/authenticated is a little absurd too.

We just need to ensure that:

• The callback works as expected with the POST parameters,
• The JS appears on node pages,
• The JS does not appear anywhere else.

Patch attached.

#2: drupal-statistics_refactor_log_tests-1326698-2.patch queued for re-testing.

Also re-categorizing as a bug and renaming, since tests as they exist now are not fully covering the behavior of the module.

#2: drupal-statistics_refactor_log_tests-1326698-2.patch queued for re-testing.

Re-roll of #2.

Minor fixes for readability in English.

Aaaand Statistics broke because these tests weren't in. All of these test improvements ended up going in via #2172859: Statistics JS and settings are not included on node pages, which fixed the module too.

Closing as a dupe, now.