BUG=swiftshader:15

Change-Id: I04a7c4206f3936c604ec623e43834c2a153fd3cb
Reviewed-on: https://chromium-review.googlesource.com/399379Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Jim Stichnoth <stichnot@chromium.org>