Remove flip_y, premultiply_alpha, unmultiply_alpha support in command buffer.

Except for client side PixelStorei, but it is an NO_OP for now.

BUG=502491
TEST=gpu bots
R=piman@chromium.org,dalecurtis@chromium.org
NOPRESUBMIT=true

Review URL: https://codereview.chromium.org/1203793003

Cr-Commit-Position: refs/heads/master@{#335957}
15 files changed