Make all fragment shader out variables require location layout qualifier. Previously, the last variable did not need a location layout qualifier if the previous variables had those. TEST=angle_unittests BUG=angleproject:1070 Change-Id: Ifb66ee52b811409f5278eaad330d6cd9b8ea059f Reviewed-on: https://chromium-review.googlesource.com/287100Tested-by: Kimmo Kinnunen <kkinnunen@nvidia.com> Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Jamie Madill <jmadill@chromium.org>
