Remove the option for animating using setInterval from the graphics benchmark

Remove the option for animating using setInterval from the graphics benchmark
https://bugs.webkit.org/show_bug.cgi?id=151283

Patch by Said Abou-Hallawa <sabouhallawa@apple.com> on 2015-11-16
Reviewed by Darin Adler.

Get rid of the option to run animation using setInterval().

* Animometer/tests/resources/main.js:
(Animator.prototype.animate):
(Benchmark):
(Benchmark.prototype.start):
(Animator.prototype.start): Deleted.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@192505 268f45cc-cd09-0410-ab3c-d52691b4dbfc