do_enclose() and other functions should use the WP API when dealing with metadata

[nacin]

do_enclose() does this:

$wpdb->insert($wpdb->postmeta, array('post_id' => $post_ID, 'meta_key' => 'enclosure', 'meta_value' => $meta_value) );

And I am not sure why. Some other functions also use $wpdb to interact with postmeta when not necessary.

[nacin]

//TODO: Tidy this ghetto code up

Done. :-)

[nacin]

[11968] caused some actions to be duplicated; more recent changesets cause more duplication.

20417.2.diff​ results in no more (add|added|delete|deleted)_(commentmeta|postmeta) actions called outside of meta.php. It results in the proper functions being used more often. It includes the work in 20417.diff​ to clean up do_enclose() as well.

[designsimply]

Tested 20417.2.diff with these steps:

1. Applied 20417.2.diff to WordPress trunk r20434
2. Created a new post with audio and video links in it, see example code below
3. Checked the feed page source to see if the proper <enclosure> tags were added

• Results: One enclosure tag was created for each unique audio or video link in the post.

Example post content with audio/video links for testing:

This post has a duplicate video link in it. Check to make sure only one enclosure tag is added for this post in the blog's feed.

<a href="http://videos.videopress.com/w0MiG12E/snow2-its-back-h2642_dvd.mp4">Let It Snow</a>

<a href="http://wpcom.files.wordpress.com/2007/01/mattmullenweg-interview.mp3">Matt Mullenweg Interview</a>

<a href="http://videos.videopress.com/w0MiG12E/snow2-its-back-h2642_dvd.mp4">Let It Snow</a>

[nacin]

Similar cleanups from mdawaffe in #14493.

[nacin]

Avoids that LIKE query.

[nacin]

In [20435]:

Use the metadata API rather than raw queries and direct do_action calls. see #20417.

[ryan]

Anything else to do here? Seems new tickets can be opened for whatever "other functions" need attention.

[nacin]

The rest of 3.diff can occur in #14493.