Media Grid, in the Edit Attachment modal: 

* Label the fields under the attachment a la the Edit Media page
* Move the audio and video previews above the info
* Remove the audio / video icon display. Unnecessary.
* Ensure that `width` and `max-width` are set for `.mejs-container`

See #24716.

Built from https://develop.svn.wordpress.org/trunk@29088


git-svn-id: http://core.svn.wordpress.org/trunk@28874 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Media Grid: 

* Don't store multiple references to the Edit Attachments frame.
* Fix keyboard navigation event delegation and proxy.
* Remove redundant function calls.

See #24716.

Built from https://develop.svn.wordpress.org/trunk@29089


git-svn-id: http://core.svn.wordpress.org/trunk@28875 1a063a9b-81f0-0310-95a4-ce76da25c4cd
General inline documentation improvements in wp-includes/post.php.

First-run. See #25412.

Built from https://develop.svn.wordpress.org/trunk@29090


git-svn-id: http://core.svn.wordpress.org/trunk@28876 1a063a9b-81f0-0310-95a4-ce76da25c4cd