[gpu] tex-2d-srgb8_alpha8-rgba-unsigned_byte.html failing on win10

conformance2/textures/image_data/tex-2d-srgb8_alpha8-rgba-unsigned_byte.html
is flaky on Builder Win10 FYI x64 Exp Release (Intel HD 630).
Suppress.

TBR=kylechar@chromium.org

Bug: 1087993
Change-Id: Icdfa404f6ab1b62fbb97b605cb6b0bb34e7d7a18
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2222881Reviewed-by: Robert Kroeger <rjkroege@chromium.org>
Reviewed-by: kylechar <kylechar@chromium.org>
Commit-Queue: Robert Kroeger <rjkroege@chromium.org>
Auto-Submit: Robert Kroeger <rjkroege@chromium.org>
Cr-Commit-Position: refs/heads/master@{#773370}

content/test/gpu/gpu_tests/test_expectations/webgl2_conformance_expectations.txt

@@ -304,6 +304,7 @@ crbug.com/1085222 [ win10 intel-0x5912 d3d11 ] deqp/functional/gles3/shaderopera
 crbug.com/1085222 [ win10 intel-0x5912 d3d11 ] deqp/functional/gles3/shaderoperator/binary_operator_01.html [ RetryOnFailure ]
 crbug.com/1085222 [ win10 intel-0x5912 d3d11 ] deqp/functional/gles3/shaderoperator/unary_operator_01.html [ RetryOnFailure ]
 crbug.com/1085222 [ win10 intel-0x5912 d3d11 ] deqp/functional/gles3/shaderoperator/unary_operator_02.html [ RetryOnFailure ]
+crbug.com/1087993 [ win10 intel-0x5912 d3d11 ] conformance2/textures/image_data/tex-2d-srgb8_alpha8-rgba-unsigned_byte.html [ RetryOnFailure ]
 
 ####################
 # Mac failures     #