Workaround isnan() on Intel drivers On some Intel drivers, calling function isnan() on highp float will get wrong answer. This patch work arounds this bug by using an expression to emulate this function. BUG=chromium:650547 Change-Id: I5bc5e0352c434f42cd2c55103a74f9f7ba51a72c Reviewed-on: https://chromium-review.googlesource.com/389834 Commit-Queue: Corentin Wallez <cwallez@chromium.org> Reviewed-by: Corentin Wallez <cwallez@chromium.org>