Skip the invalid and flaky networkState_during_progress.html W3C test.

Per the bug discussion, this test is invalid. Since it is part of third party
tests, we must wait for it to be removed upstream. In the meantime, skip it.

BUG=306249
R=philipj@opera.com

Review URL: https://codereview.chromium.org/184233008

git-svn-id: svn://svn.chromium.org/blink/trunk@168677 bbb929c8-8fbe-4397-9dbb-9b2b20218538