Also adds a test for an integer overflow in DrawArrays validation.

BUG=602737

Change-Id: I71c5bd155cf919964f46e2b0b48267253cab91eb
Reviewed-on: https://chromium-review.googlesource.com/716841Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>