Move Featured Media UI to Featured Image Metabox

[rclations]

fixes #698

The Problem

• Featured image override checkbox is hidden at the bottom of the featured image selection modal
• The wording on the checkbox is confusing
• Options in the image selection modal should apply to that specific image - this checkbox is applies to the post (not the image itself)
• The existing "Set Featured Media" button is located above the wysiwyg editor. This area is generally used for shortcode buttons to be used within the wysiwyg editor.

Proposed Solution

The featured media metabox was removed so we could build our own button with additional options for featured video, embed, gallery, etc.

This PR adds a new featured media metabox and moves the "Set Featured Media" button there.

[aschweigert]

@rclations same issue here :/ I'm not able to check out this branch to review because it's on your fork. Can you move that branch over here so I can do some final review/cleanup before merging?

[rclations]

@aschweigert can you access it now? I just checked the new "allow edits from maintainers" feature

[aschweigert]

ok, this lgtm, a couple to-do items before merging:

• need to make the featured media templates translatable (currently nothing in there is)
• consider refactoring the duplicative featured media functions (there's a set for each type of featured media that do nearly the same thing, let's try to see if we can refactor that and make it a bit cleaner)

[rclations]

should be all set, but @aschweigert or @benlk, could you give this a quick review before I merge?

[benlk]

I'm getting a featured-media.min.js?ver=4.6.1:1 Uncaught TypeError: Cannot read property 'replace' of undefined when running with LARGO_DEBUG set to False, but not when True.

With True, it works pretty well, but should probably be higher in the stack on the page:

[aschweigert]

@jackbrighton we'll need docs coverage for this since we're moving peoples' button. Let's make sure that gets done before we ship 0.5.5

[benlk]

Found source of bugs in #1322 with non-image featured media.

[benlk]

partials/hero-featured-video is not a file that exists.

This line should use $template_slug = 'embed', to match the old code:

if (in_array($featured_media['type'], array('embed-code', 'video'))) {
    $ret = largo_get_featured_embed_hero($post->ID,$classes);

[benlk]

If we're adding partials/hero-featured-embed.php to the list of things that get rendered with this context, then $featured_media and $gallery_ids need to be passed in this array if that's appropriate to the rendering.

[benlk]

The code changes in this PR included a lot of things that weren't mentioned in the pull request's description. ☹️