Restore AJAX data source for Chosen

[danielbachhuber]

In doing so, we can avoid the performance issues with large taxonomies

See #244

[mboynes]

This comment doesn't seem to apply, but there should be an option to group by taxonomy.

[mboynes]

I'm going to dive into this later this afternoon; I want to give it some more thought. Thanks for the PR!

[danielbachhuber]

Not done quite yet — still plugging things back together.

[mboynes]

Ah OK. Thanks, let me know when it's ready for testing and review.

[danielbachhuber]

@mboynes @netaustin I'd be interested in your initial thoughts on this. The UX needs more work, but I think this is a better approach than #251.

@mboynes Let me know what tests you're thinking of.

[danielbachhuber]

Bump @mboynes

[mboynes]

@danielbachhuber Sorry for the delay, I'm finally getting around to this. This looks great. I ran into some styling issues and while fixing them took the opportunity to update chosen to 1.3.0. I put that in #275 (as a PR to merge into this one).

Re:what to test, that's a good question. I think we should be able to test 95% of it without having to fake an ajax request, since the ajax responder uses Fieldmanager_Datasource::get_items_for_ajax() for the heavy lifting. Worth mentioning that I just wrote a bunch of tests in #274, so perhaps we should merge that before starting on tests for this one. I'd like to get that merged within the next day or two, and then I'd like to get this PR merged this week.

[danielbachhuber]

🏈 not worth pursuing this. Select2 is the way to go.