Remove unused unittestresults file.

The unittestresults.py (and related unittest) was used in the
old WebKit days. We can safely remove it.

BUG=none

Review URL: https://codereview.chromium.org/646473002

git-svn-id: svn://svn.chromium.org/blink/trunk@183545 bbb929c8-8fbe-4397-9dbb-9b2b20218538