Remove remaining title attributes from default-widgets.php, with the exception of the one on the link to WordPress.org. fixes #26552.

Built from https://develop.svn.wordpress.org/trunk@29338


git-svn-id: http://core.svn.wordpress.org/trunk@29118 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Bail on `update_user_meta()` when `$object_id` is non-numeric.

Adds unit test.

Props jacklenox, wonderboymusic.
Fixes #28315.

Built from https://develop.svn.wordpress.org/trunk@29339


git-svn-id: http://core.svn.wordpress.org/trunk@29119 1a063a9b-81f0-0310-95a4-ce76da25c4cd