Remove dom_perf tests.

Blink has a copy of dom_perf tests.
They are all skipped, because we run them for chromium.

BUG=

Review URL: https://chromiumcodereview.appspot.com/23618046

git-svn-id: svn://svn.chromium.org/blink/trunk@158171 bbb929c8-8fbe-4397-9dbb-9b2b20218538