Respect DisabledByDefault in parent configs

[aroben]

d956705 changed Config initialization such that Config#deprecation_check was called before resolving inheritance. Config#deprecation_check causes Config#for_all_cops to be lazily initialized to a new hash disconnected from Config's primary hash. Config#for_all_cops would thus not reflect any settings inherited from parent configs.

Essentially, it's an error for Config#for_all_cops to be called before inheritance is resolved. Perhaps this code could be made more robust. For now I've just rearranged config initialization such that things happen in the same order as prior to d956705.

/cc @NickLaMuro

---

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• Wrote good commit messages.
• Commit message starts with [Fix #issue-number] (if the related issue exists).
• Used the same coding conventions as the rest of the project.
• Feature branch is up-to-date with master (if not - rebase it).
• Squashed related commits together.
• Added tests.
• Added an entry to the Changelog if the new code introduces user-observable changes. See changelog entry format.
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  and description in grammatically correct, complete sentences.
• Updated cop documentation with rake generate_cops_documentation (required only when you've added a new cop or changed the configuration/documentation of an existing cop).

[NickLaMuro]

So I think the tests failing on the test I wrote in that commit are the reason I picked the order that I did. That all said, it has been so long since I looked at #3421 that I would have to take a bit to re-familiarize myself with the whole config setup to tell you for sure.

Regardless... sorry for breaking this... 😞

[jonas054]

The failing test case is about resolving configuration where the namespace is missing, i.e., we have LineLength rather than Metrics/LineLength. So the call to config.add_missing_namespaces must be done before the resolve_... methods. And maybe a second time after those calls.

[aroben]

Whoops, I clearly forgot to run the whole test suite before opening this PR. I've fixed the failures and force-pushed. How's it look now?

[jonas054]

👍 LGTM. You just need to rebase because I'm so slow with the reviewing.

[aroben]

Rebased!