Add a perf test for binding buffers. BUG=angleproject:1639 Change-Id: I42da2acdb7c99116c4418a2f71d65d72d328d641 Reviewed-on: https://chromium-review.googlesource.com/428572 Commit-Queue: Geoff Lang <geofflang@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>