Revert "Cut down the SVG test times by half"

This reverts r154821 as it increases test flakiness.

R=pdr@chromium.org
BUG=262332

Review URL: https://codereview.chromium.org/20110003

git-svn-id: svn://svn.chromium.org/blink/trunk@154856 bbb929c8-8fbe-4397-9dbb-9b2b20218538