We were using a formula that didn't work for some of the clipping tests. Bug: angleproject:2601 Change-Id: I60d965c2701656ad590c3b250c2cc777fb432421 Reviewed-on: https://chromium-review.googlesource.com/1194919Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Jamie Madill <jmadill@chromium.org>
