Check that search value is scalar before parsing.

Prevents PHP notices when non-scalar values are passed.

Includes unit tests.

Props tivnet.
Fixes #29736.
Built from https://develop.svn.wordpress.org/trunk@29912


git-svn-id: http://core.svn.wordpress.org/trunk@29666 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add a 6th (!) attribute to `wp_get_attachment_link()` to allow `aria-describedby` to be added to gallery output.

Props joedolson, DrewAPicture, rianrietveld.
Fixes #27402.

Built from https://develop.svn.wordpress.org/trunk@29914


git-svn-id: http://core.svn.wordpress.org/trunk@29667 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Cache `get_term_by()` calls:

* Add a helper function, `wp_get_last_changed()`, to retrieve a last-modified timestamp by cache group
* When caching a term, also make cache entries for slug and name via `slug:{$term_id}` and `name:{$term_id}` keys in the `$taxonomy:$last_changed` bucket that reference the term_id
* In `clean_term_cache()` and `update_term_cache()`, respect `$_wp_suspend_cache_invalidation`
* Original term cache entries maintain BC

Adds unit tests.

Props wonderboymusic, tollmanz, boonebgorges.
Fixes #21760.

Built from https://develop.svn.wordpress.org/trunk@29915


git-svn-id: http://core.svn.wordpress.org/trunk@29668 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In `wp.Uploader`, when `uploader:ready` is triggered, set `ready` to `true` on the instance. This allows media workflows to check for an existing uploaded instance when opening.

Without this check, workflows might wait for `uploader:ready`, which could already have been fired. This would result in an unresponsive editor dropzone.

Fixes #29689.

Built from https://develop.svn.wordpress.org/trunk@29917


git-svn-id: http://core.svn.wordpress.org/trunk@29669 1a063a9b-81f0-0310-95a4-ce76da25c4cd