Suppress WebGL 1 failures on Mac DTKs

Suppresses the currently failing WebGL 1 tests on the ARM-based Mac
DTKs.

Bug: 1130760, 1130759, 1130758, 1130703
Change-Id: I6a4ff7ebef48af09562cd9f6fd0a210b1256cc26
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2422503
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Commit-Queue: Yuly Novikov <ynovikov@chromium.org>
Auto-Submit: Brian Sheedy <bsheedy@chromium.org>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809091}

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

@@ -7,6 +7,7 @@
 # tags: [ android-chromium android-webview-instrumentation ]
 # tags: [ debug debug-x64 release ]
 # tags: [ amd amd-0x6613 amd-0x699f amd-0x679e
+#         apple apple-apple-a12z
 #         intel intel-0xa011 intel-0xa2e
 #         nvidia nvidia-0x1cb3 nvidia-0x2184 nvidia-0xfe9
 #         arm-mali-t860
@@ -472,6 +473,15 @@ crbug.com/angleproject/4846 [ mac metal passthrough nvidia ] conformance/renderi
 crbug.com/angleproject/4846 [ mac metal passthrough nvidia ] conformance/rendering/more-than-65536-indices.html [ Failure ]
 crbug.com/angleproject/4846 [ mac metal passthrough nvidia ] conformance/textures/misc/texture-mips.html [ Failure ]
 
+# Mac ARM-based DTKs
+crbug.com/1130703 [ mac apple-apple-a12z no-passthrough ] conformance/textures/misc/texture-copying-and-deletion.html [ Failure ]
+crbug.com/1130703 [ mac apple-apple-a12z no-passthrough ] conformance/textures/misc/texture-copying-feedback-loops.html [ Failure ]
+crbug.com/1130758 [ mac apple-apple-a12z ] conformance/extensions/webgl-depth-texture.html [ Failure ]
+crbug.com/1130759 [ mac apple-apple-a12z metal ] conformance/rendering/rendering-stencil-large-viewport.html [ Failure ]
+crbug.com/1130759 [ mac apple-apple-a12z metal ] conformance/textures/misc/texture-mips.html [ Failure ]
+crbug.com/1130760 [ mac apple-apple-a12z metal ] conformance/extensions/webgl-draw-buffers.html [ Failure ]
+crbug.com/1130760 [ mac apple-apple-a12z metal ] conformance/ogles/GL/discard/discard_001_to_002.html [ Failure ]
+
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 # Linux failures   #
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