This improves the appearance of various form controls in the admin and addresses some visual inconsistencies in WordPress 5.3.
Props afercia, audrasjb, jameskoster, GDragoN, azaozz, michaelarestad, murgroland, SamuelFernandez, chetan200891, veminom, dlh.
Merges [46866] to the 5.3 branch.
Fixes#48420.
Built from https://develop.svn.wordpress.org/branches/5.3@46867
git-svn-id: http://core.svn.wordpress.org/branches/5.3@46667 1a063a9b-81f0-0310-95a4-ce76da25c4cd