Add missing properties to ::first-letter whitelist

Several properties were missed the first time the CSSProperty whitelist
was added for ::first-letter pseudo elements.
This change ensures that we're at least equivalent to Firefox's implementation.

BUG=369010

Review URL: https://codereview.chromium.org/266953002

git-svn-id: svn://svn.chromium.org/blink/trunk@173370 bbb929c8-8fbe-4397-9dbb-9b2b20218538