Plugin install: Make plugin groups translatable.

props ocean90 for initial patch.
fixes #29092.
Built from https://develop.svn.wordpress.org/trunk@29477


git-svn-id: http://core.svn.wordpress.org/trunk@29255 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Fix the `wp-settings-*` cookies used in getUserSetting()/setUserSetting(). They should be set without `COOKIE_DOMAIN` to work properly for sub-domains. Fixes #29095.
Built from https://develop.svn.wordpress.org/trunk@29478


git-svn-id: http://core.svn.wordpress.org/trunk@29256 1a063a9b-81f0-0310-95a4-ce76da25c4cd