Add #version 300 es to ESSL output when needed BUG=angleproject:953 Change-Id: Ib9e45fab1d35f8c78abd0ac2209ac4f63afe4465 Reviewed-on: https://chromium-review.googlesource.com/261170 Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Olli Etuaho <oetuaho@nvidia.com> Reviewed-by: Zhenyao Mo <zmo@chromium.org>