Fix false positive for Rails/LexicallyScopedActionFilter when action methods are delegated

[vlad-pisanov]

Fixes: #1447

Currently, Rails/LexicallyScopedActionFilter only looks for explicitly defined (def) action methods, and aliased action methods (alias, alias_method), but not action methods defined via delegation delegate :my_action, to: ...

This PR fixes that.

---

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[Earlopain]

Getting into this situation in the first place seems wrong to me, I don't think I would enjoy using delegation for controller actions. But, this is a fix regardless of that.

In my opinion Rails/Delegate should have special handling for controllers. What do you think?

[vlad-pisanov]

@Earlopain I'm down with disabling Rails/Delegate on the controller directories by default. Delegated actions can be useful but I wouldn't want to be forced into using them.

[koic]

Thanks!

[koic]

I'm down with disabling Rails/Delegate on the controller directories by default.

I agree.

[Earlopain]

#1454