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.

Built from https://develop.svn.wordpress.org/trunk@30153


git-svn-id: http://core.svn.wordpress.org/trunk@30153 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In `WP_List_Table`, add a property, `$modes`, to allow `WP_Media_List_Table` to inherit `->view_switcher()`.

See #30224.

Built from https://develop.svn.wordpress.org/trunk@30154


git-svn-id: http://core.svn.wordpress.org/trunk@30154 1a063a9b-81f0-0310-95a4-ce76da25c4cd