Remove the Chromium-specific helper from run_webkit_tests.py
https://bugs.webkit.org/show_bug.cgi?id=114996

Patch by Seokju Kwon <seokju.kwon@gmail.com> on 2013-04-24
Reviewed by Dirk Pranke.

* Scripts/webkitpy/layout_tests/run_webkit_tests.py:
(parse_args):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@149046 268f45cc-cd09-0410-ab3c-d52691b4dbfc