Move SVGNames to Python

This CL removes the dependency on make_names.pl from SVG. After this CL, there
is only one more client of make_names.pl to remove.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/35423004

git-svn-id: svn://svn.chromium.org/blink/trunk@160366 bbb929c8-8fbe-4397-9dbb-9b2b20218538