Don't allow unary operators on void types. BUG=900058 Change-Id: Ice8976ddd9cbc9c90162cf7fae2b8f91ddcfcef3 Reviewed-on: https://chromium-review.googlesource.com/c/1344590 Reviewed-by: Corentin Wallez <cwallez@chromium.org> Commit-Queue: Geoff Lang <geofflang@chromium.org>