Remove unused Perl in-file support

All the clients of this code have been converted to Python.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/40713002

git-svn-id: svn://svn.chromium.org/blink/trunk@160486 bbb929c8-8fbe-4397-9dbb-9b2b20218538