Remove ENABLE_SVG references from core/html/

Most references were already removed in r150629, this just cleans
up a few stragglers.

R=eseidel@chromium.org, pdr@chromium.org
BUG=240006

Review URL: https://codereview.chromium.org/15937013

git-svn-id: svn://svn.chromium.org/blink/trunk@151417 bbb929c8-8fbe-4397-9dbb-9b2b20218538
5 files changed