Skip imported/web-platform-tests/custom-elements/.../no-registry-test.html

As this test requires http server to run, skip this test in imported/
directory and have the same test in http/.

Review URL: https://codereview.chromium.org/581543002

git-svn-id: svn://svn.chromium.org/blink/trunk@182558 bbb929c8-8fbe-4397-9dbb-9b2b20218538