Clarify inline documentation for the `_is_valid_nav_menu_item()` and `wp_get_nav_menu_items()` in wp-includes/nav-menu.php.

Props morganestes for the initial patch.
Fixes #29914.

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git-svn-id: http://core.svn.wordpress.org/trunk@29628 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add missing labels to category filter dropdowns.

props afercia.
fixes #29921.
Built from https://develop.svn.wordpress.org/trunk@29870


git-svn-id: http://core.svn.wordpress.org/trunk@29629 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Remove "View" prefix from category filter dropdowns, for consistency with [27626].

props afercia.
see #29921.
Built from https://develop.svn.wordpress.org/trunk@29871


git-svn-id: http://core.svn.wordpress.org/trunk@29630 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add missing label to comment type filter dropdown.

props afercia.
fixes #29922.
Built from https://develop.svn.wordpress.org/trunk@29872


git-svn-id: http://core.svn.wordpress.org/trunk@29631 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix whitespace issues in [29781]. Remove a redundant comment.

props miqrogroove.
see #29557.
Built from https://develop.svn.wordpress.org/trunk@29873


git-svn-id: http://core.svn.wordpress.org/trunk@29632 1a063a9b-81f0-0310-95a4-ce76da25c4cd