AngularLoader - Emit warning when setModules method is used.

[colemanw]

Overview

Emit warning when extensions do something that could potentially cause problems with other extensions.

[civibot]

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[totten]

I'm good with this change, with a caveat.

The situation is that we are changing recommended usage/protocol.

• Old protocol/Unique loaders:new AngularLoader()... ->setModules(['my','list'])
• New protocol/Shared loader: Civi::service('angularjs.loader')...->addModules(['my','list'])

(Speaking of which.... on r-doc, this needs an update for civicrm-dev-docs/docs/framework/angular/loader.md.)

Marking setModules() as deprecated has the effect of emitting a warning on everything that uses the old protocol, which is good. Because AFAICS everything that uses the old protocol would be better served by the new protocol.

OTOH, the method setModules() isn't bad or complex. There are hypothetically valid ways to use setModules() in the new protocol (e.g. filtering/substituting - setModules(applyMyFilter(getModules()))). But that's so obscure/speculative... it's really not worth spending any time on it unless someone actually needs that case.

So I'm +1 to mark this deprecated, owing to the real-world/foreseeable impact. But if (in 3 months time) somebody comes around with a good/concrete scenario, then setModules() could be rehabilitated.