This method is deprecated in Rails 5.1 because its behavior will be
different in `before` and `after` callbacks.
We're replacing the deprecated `attribute_changed?` and `attribute_was`
methods with `saved_change_to_attribute?` and
`attribute_before_last_save` during `after_save` callbacks.
https://github.com/rails/rails/pull/32835/
We were very inconsistent regarding these rules.
Personally I prefer no empty lines around blocks, clases, etc... as
recommended by the Ruby style guide [1], and they're the default values
in rubocop, so those are the settings I'm applying.
The exception is the `private` access modifier, since we were leaving
empty lines around it most of the time. That's the default rubocop rule
as well. Personally I don't have a strong preference about this one.
[1] https://rubystyle.guide/#empty-lines-around-bodies
