Make Style/AccessModifierDeclarations disabled by default

[wata727]

Follow up of #5953, #6032

I think it is too difficult to enforce group (default) style by default because it doesn't work for some methods.

For example, def_delegator doesn't work when using group style:

require 'forwardable'

class Cat
  def meow
    puts "Meow!"
  end
end

class CatCage
  extend Forwardable

  def initialize(cat)
    @cat = cat
  end

  private

  def_delegator :@cat, :meow
end

[8] pry(main)> CatCage.new(Cat.new).meow
Meow!
=> nil

This is because def_delegator defines a method by self.module_eval. Forcing group styles by default may be misleading for the above problems.

Maybe it is needed to add such methods to the whitelist and exclude them from inspection, but it seems to be difficult for me.

First of all, I think it should make this cop disabled by default and help users confused by this cop. WDYT? @brandonweiss

---

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• Wrote good commit messages.
• Commit message starts with [Fix #issue-number] (if the related issue exists).
• 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.
• The PR relates to only one subject with a clear title
  and description in grammatically correct, complete sentences.
• Run rake default or rake parallel. It executes all tests and RuboCop for itself, and generates the documentation.

[brandonweiss]

I think it’s probably best to improve the cop, not disable it by default. The RuboCop team has expressed a dislike of cops that are disabled by default (which I agree with) as practically no one goes through and enables them, effectively meaning they might as well not exist.

I think the improvement of adding a whitelist of tokens that accessors can be inlined before while using group configuration probably makes the most sense.

[wata727]

Thanks for your opinion. This approach seems unacceptable to the team, so I will close it once.