Remove webgl-compressed-texture-s3tc-srgb.html suppression.

Remove suppression on Win / OpenGL / passthrough / Intel. Bug has been
fixed in ANGLE.

Bug: 1048861
Change-Id: I2fa696eea8d2dd08c325c172769041865b2d1e9e
No-Try: True
Tbr: enga@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2040062
Commit-Queue: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Cr-Commit-Position: refs/heads/master@{#738722}

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

@@ -120,7 +120,6 @@ crbug.com/602688 [ opengl win passthrough intel ] conformance2/glsl3/vector-dyna
 # Passthrough command decoder / Windows / OpenGL / Intel
 # Recent regressions on passthrough command decoder
 crbug.com/1048861 [ opengl win passthrough intel ] conformance/extensions/webgl-compressed-texture-astc.html [ Failure ]
-crbug.com/1048861 [ opengl win passthrough intel ] conformance/extensions/webgl-compressed-texture-s3tc-srgb.html [ Failure ]
 # This case causes no-over-optimization-on-uniform-array fail.
 crbug.com/884210 [ opengl win passthrough intel ] conformance/ogles/GL/gl_FragCoord/gl_FragCoord_001_to_003.html [ Skip ]