Remove more dead code in applyProperty(CSSPropertyFont)

The FontValue handling code has been dead since
http://trac.webkit.org/changeset/100273

If this code were not dead, it would be exercised
by the fast/canvas/crash-set-font.html test
added by jchaffraix in
http://trac.webkit.org/changeset/96122

BUG=237268
R=dglazkov@chromium.org

Review URL: https://codereview.chromium.org/19678002

git-svn-id: svn://svn.chromium.org/blink/trunk@154428 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Don't set firstPartyForCookies on every document.

We can look it up off the request that created the main frame's document.

Also, delete logic for setting firstPartyForCookies on download ResourceRequests,
since we don't every look at it after setting it.

BUG=none

Review URL: https://chromiumcodereview.appspot.com/19444002

git-svn-id: svn://svn.chromium.org/blink/trunk@154429 bbb929c8-8fbe-4397-9dbb-9b2b20218538