Disable segments-from-data-url as part of two-sided URL patch.

This can be rebased and re-enabled once the chrome side lands.

BUG=346132
TBR=brettw@chromium.org

Review URL: https://codereview.chromium.org/177843016

git-svn-id: svn://svn.chromium.org/blink/trunk@167929 bbb929c8-8fbe-4397-9dbb-9b2b20218538