Allow the view_config to be passed into the document_presenter helper and DocumentComponent constructor

[cbeer]

This allows downstream applications (and e.g. gems like spotlight) a little more flexibility in how they use these.

[jcoyne]

Is there really a case where presenter is nil? Wouldn't we also need to deal with that in the delegate :field_presenters?

[cbeer]

I don't know. Someone thought so in all the renders_one blocks above, but not in the before_render.

[jcoyne]

Can you explain why downstream apps need more flexibility? In order to do what?

It seems that this would allow the presenter.view_config to be different than DocumentComponent#view_config and that seems like a lot of complexity.

[cbeer]

Spotlight is a good example where its use of document presenters and components doesn't neatly align with Blacklight's limited notion of search results and single document pages, and where document_presenter_class is really a bad fit:

blacklight/app/helpers/blacklight/document_helper_behavior.rb

Lines 68 to 74 in 023c1b0

	def document_presenter_class(_document = nil)
	case action_name
	when 'show', 'citation'
	blacklight_config.view_config(:show, action_name: action_name).document_presenter_class
	else
	blacklight_config.view_config(document_index_view_type, action_name: action_name).document_presenter_class
	end

[jcoyne]

@cbeer It seems like what Spotlight has right now is working... so what do you want it to look like?

[cbeer]

Yes, spotlight, blacklight-gallery and who-knows-what-else could all provide their own document_presenter implementations to just get the document presenter instance they actually want. It seems like an anti-pattern to force each gem to do that when we could have a standardized implementation here for just a tiny change.

[jcoyne]

So the main thing here is the addition of view_config&.document_presenter_class in #document_presenter? That seems like a good change. Do you think we should deprecate the call to document_presenter_class helper method? Do we still need two ways to do this?