In `wp_xmlrpc_server` methods, for comprehensibility:

* initialize arrays in loops, instead of overriding an uninitialized array each time
* in `->blogger_getRecentPosts()` and `->mw_getRecentPosts()`, remove the extra loops by only setting one `array`

See #30224.


git-svn-id: https://develop.svn.wordpress.org/trunk@30153 602fd350-edb4-49c9-b593-d223f7449a82
In `WP_List_Table`, add a property, `$modes`, to allow `WP_Media_List_Table` to inherit `->view_switcher()`.

See #30224.


git-svn-id: https://develop.svn.wordpress.org/trunk@30154 602fd350-edb4-49c9-b593-d223f7449a82
Improve some `post_status`-related documentation.

Props ericlewis.
See #30230.


git-svn-id: https://develop.svn.wordpress.org/trunk@30155 602fd350-edb4-49c9-b593-d223f7449a82
Display error message when Media Library upload fails.

Props gcorne.
Fixes #29891.


git-svn-id: https://develop.svn.wordpress.org/trunk@30156 602fd350-edb4-49c9-b593-d223f7449a82
Check `$_current_page` before using it in `Walker_Page->start_el()`.

Props jeremyfelt.
Fixes #26901.


git-svn-id: https://develop.svn.wordpress.org/trunk@30157 602fd350-edb4-49c9-b593-d223f7449a82
All duplicate slugs across different post types.

Adds unit test.

Props mboynes, nacin.
Fixes #18962.


git-svn-id: https://develop.svn.wordpress.org/trunk@30158 602fd350-edb4-49c9-b593-d223f7449a82
Allow `get_pages()`, with `child_of` passed to it, to work with interrupted hierarchies.

Adds unit test.
Fixes #18962.


git-svn-id: https://develop.svn.wordpress.org/trunk@30159 602fd350-edb4-49c9-b593-d223f7449a82