Revert of WebGL: use storage texture for DrawingBuffer only if CMAA is enabled. (patchset #3 id:60001 of https://codereview.chromium.org/2131863003/ )

Reason for revert:
ATI GPU bots became green, no matter this CL. ATI GPU bot might be in bad shape for some reasons.
So revert this redundant speculative fix.

Original issue's description:
> WebGL: use storage texture for DrawingBuffer only if CMAA is enabled.
>
> It's because Linux ATI bot fails
> WebglConformance.conformance_textures_misc_tex_image_webgl
> When finding the solution for ATI driver, rollback this patch.
>
> BUG=557848
> TEST=WebglConformance.conformance_textures_misc_tex_image_webgl
> CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel;tryserver.chromium.win:win_optional_gpu_tests_rel
>
> Committed: https://crrev.com/65f8f6c737278a80acee2bcd407d1fdc15426fa8
> Cr-Commit-Position: refs/heads/master@{#404514}

TBR=piman@chromium.org,kbr@chromium.org,zmo@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=557848

Review-Url: https://codereview.chromium.org/2133253003
Cr-Commit-Position: refs/heads/master@{#404563}
1 file changed