ApplicationRecord - temporarily add .decorate and self.decorate

[himdel]

This is UI code that should live in the UI, but that requires a few more steps first.

In the mean time, we either have to keep patching ApplicationRecord and deal with the autoloader, or just add it to ApplicationRecord directly :).

This is a follow up to ManageIQ/manageiq-ui-classic#237 (which solved this by an initializer, which doesn't work with rails' autoloading in development mode).

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Please merge together with ManageIQ/manageiq-ui-classic#506 (either will break without the other).

@miq-bot add_label technical debt, ui, euwe/no

[himdel]

Ping @Fryguy , @chrisarcand, @martinpovolny .. this is meant as a temporary solution for the autoloader issues, which will get removed in the second round of decorator refactoring.

(Unfortunately can't do that right away, since we're blocked by #14040 for now.)

[miq-bot]

Checked commit https://github.com/himdel/manageiq/commit/86c9a35bc303287194a8957b931d80177265ef12 with ruby 2.2.6, rubocop 0.47.1, and haml-lint 0.20.0
1 file checked, 0 offenses detected
Everything looks good. 🍪

[martinpovolny]

I understand the concerns about decorating models for the sake of UI and altering ApplicationRecord. But it will take some time before we are able to untie the frontend from the backend and before we do that we have a log of cleaning work to do in the UI.

To move forward we need this.

Unless someone is strongly againts this (and can help in finding a better solution) I'd merge this.

[chrisarcand]

Seems fine temporarily, to me. 🙏 Please let it be only temporary; as discussed, true decoration really should not need anything like this.

👍