Remove failing expectation for virtual/web-animations-css/animations/3d/state-at-end-event-transform.html

This test has been passing reliably for some time.

R=dstockwell

Review URL: https://codereview.chromium.org/36463003

git-svn-id: svn://svn.chromium.org/blink/trunk@160324 bbb929c8-8fbe-4397-9dbb-9b2b20218538