GLES1: Point rasterization (partial implementation) - Not included: Smooth points - GL_OES_point_sprite - Update test expectations. Note: due to different random sampling, edge cases were hit in UserClip. Disabling that test for now. BUG=angleproject:2306 Change-Id: If8367bc3321804b3299d3bc381d6a8e236754baa Reviewed-on: https://chromium-review.googlesource.com/1101910 Reviewed-by: Corentin Wallez <cwallez@chromium.org> Commit-Queue: Lingfeng Yang <lfy@google.com>