image-with-origin-header.html now passes on Win

Looks like https://codereview.chromium.org/288493006 did indeed fix this, see:
http://test-results.appspot.com/dashboards/flakiness_dashboard.html#group=%40ToT%20Blink&tests=http%2Ftests%2Fimages%2Fimage-with-origin-header.html

R=yoav@yoav.ws,abarth@chromium.org
BUG=341435

Review URL: https://codereview.chromium.org/279403009

git-svn-id: svn://svn.chromium.org/blink/trunk@174010 bbb929c8-8fbe-4397-9dbb-9b2b20218538