Reason for revert:
This doesn't work on Mac Intel (most likely a driver bug)
Original issue's description:
> Turn on seamless cubemap by default on Desktop GL for ES3.
>
> BUG=597794
> TEST=deqp/texturefiltering_cube_*
> R=piman@chromium.org
> CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_optional_gpu_tests_rel
>
> Committed: https://crrev.com/39a22dc8028987efa3ca24135922841d2d2d387c
> Cr-Commit-Position: refs/heads/master@{#383362}
TBR=piman@chromium.org,piman@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=597794
Review URL: https://codereview.chromium.org/1840553002
Cr-Commit-Position: refs/heads/master@{#383405}
0e22e7e8fe