Remove LayoutTest animations/animation-direction-reverse-fill-mode-pause.html

This test is incorrect and flaky, and it's not clear what it's trying to test.

This test checks the animated value after the animation has ended. Since the
animation does not use fill, the animated value should be the underlying value,
but the test checks for the 'to' value.

This test is also inherently flaky, as it uses the runAnimationTest() helper
without the internals pause API. While it is not currently failing on the bots,
it fails repeatably when run locally in isolation.

Finally, it's not clear what the test is trying to test. It pauses the
animation after it has completed, but it's not clear why. The other aspects of
the test are well covered in other tests.

R=dstockwell

Review URL: https://codereview.chromium.org/39373002

git-svn-id: svn://svn.chromium.org/blink/trunk@160422 bbb929c8-8fbe-4397-9dbb-9b2b20218538