Make sure to use 3-digit x.x.x style for two 3.9.0 `@since` versions.

Props netweb.
Fixes #28446.

Built from https://develop.svn.wordpress.org/trunk@28658


git-svn-id: http://core.svn.wordpress.org/trunk@28476 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix SQL generation when `meta_query` has an `'relation' => 'OR'` for its queries and wants to `'orderby' => 'meta_value'`.

Adds unit test.

Props jackreichert.
Fixes #25538.


Built from https://develop.svn.wordpress.org/trunk@28659


git-svn-id: http://core.svn.wordpress.org/trunk@28477 1a063a9b-81f0-0310-95a4-ce76da25c4cd