[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/+/2219030Reviewed-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}

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

@@ -371,6 +371,7 @@ 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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