Revert "[gpu/mac] suppress failing webgl_canvas/tex-3d-rgb8ui-rgb_integer-unsigned_byte.html"

This reverts commit 79c629a2.

Reason for revert: underlying flaky GPU process crash has been worked around.

Original change's description:
> [gpu/mac] suppress failing webgl_canvas/tex-3d-rgb8ui-rgb_integer-unsigned_byte.html
> 
> On Mac Asan,
> conformance2/textures/webgl_canvas/tex-3d-rgb8ui-rgb_integer-unsigned_byte.html
> started failing. Suppress the test.
> 
> TBR=kbr@chromium.org
> 
> Bug: 1087083
> Change-Id: I0ece6b3d187199308e3c486f7bf927b07c59cdbf
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2219030
> Reviewed-by: Robert Kroeger <rjkroege@chromium.org>
> Commit-Queue: Robert Kroeger <rjkroege@chromium.org>
> Auto-Submit: Robert Kroeger <rjkroege@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#772444}

TBR=rjkroege@chromium.org,kbr@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 1087083
Change-Id: Ibfda1b3e7e359f07987edcd78eb76c6309770ba2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2229009Reviewed-by: Kenneth Russell <kbr@chromium.org>
Commit-Queue: Kenneth Russell <kbr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#774789}

content/test/gpu/gpu_tests/test_expectations/webgl_conformance_expectations.txt

@@ -367,7 +367,6 @@ crbug.com/982294 [ mac passthrough nvidia ] conformance/textures/misc/texture-co
 crbug.com/1059760 [ mac asan ] conformance/textures/image_bitmap_from_video/* [ RetryOnFailure ]
 crbug.com/1059760 [ mac no-passthrough asan ] conformance/textures/misc/texture-corner-case-videos.html [ RetryOnFailure ]
 crbug.com/1059760 [ mac asan ] conformance/textures/video/* [ RetryOnFailure ]
-crbug.com/1087083 [ mac passthrough amd asan ] conformance2/textures/webgl_canvas/tex-3d-rgb8ui-rgb_integer-unsigned_byte.html [ Failure ]
 
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 # Linux failures   #