Remove webgl_conformance_metal_passthrough_tests from Mac NVIDIA.

Flaking substantially while collecting GPU info. A workaround may be
possible, but need to suppress the flakiness first.

Bug: 1158857
Change-Id: I80b021024dc83a63e5a48516e020819186d25bf8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2593759
Commit-Queue: Kenneth Russell <kbr@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Yuly Novikov <ynovikov@chromium.org>
Auto-Submit: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#837319}

testing/buildbot/chromium.gpu.fyi.json

@@ -23369,43 +23369,6 @@
         },
         "test_id_prefix": "ninja://chrome/test:telemetry_gpu_integration_test/"
       },
-      {
-        "args": [
-          "webgl_conformance",
-          "--show-stdout",
-          "--browser=release",
-          "--passthrough",
-          "-v",
-          "--extra-browser-args=--enable-logging=stderr --js-flags=--expose-gc --use-gl=angle --use-angle=metal --use-cmd-decoder=passthrough --force_high_performance_gpu",
-          "--read-abbreviated-json-results-from=../../content/test/data/gpu/webgl_conformance_tests_output.json"
-        ],
-        "isolate_name": "telemetry_gpu_integration_test",
-        "merge": {
-          "args": [],
-          "script": "//testing/merge_scripts/standard_isolated_script_merge.py"
-        },
-        "name": "webgl_conformance_metal_passthrough_tests",
-        "resultdb": {
-          "enable": true
-        },
-        "should_retry_with_patch": false,
-        "swarming": {
-          "can_use_on_swarming_builders": true,
-          "containment_type": "AUTO",
-          "dimension_sets": [
-            {
-              "gpu": "10de:0fe9",
-              "hidpi": "1",
-              "os": "Mac-10.14.6",
-              "pool": "chromium.tests.gpu"
-            }
-          ],
-          "idempotent": false,
-          "service_account": "chromium-tester@chops-service-accounts.iam.gserviceaccount.com",
-          "shards": 3
-        },
-        "test_id_prefix": "ninja://chrome/test:telemetry_gpu_integration_test/"
-      },
       {
         "args": [
           "webgl_conformance",

testing/buildbot/test_suite_exceptions.pyl

@@ -2807,6 +2807,12 @@
       'Win7 FYI Release (AMD)',
     ],
   },
+  'webgl_conformance_metal_passthrough_tests': {
+    'remove_from': [
+      # crbug.com/1158857: re-enable if Metal shader cache workaround is added.
+      'Mac FYI Retina Release (NVIDIA)',
+    ],
+  },
   'webgl_conformance_tests': {
     'modifications': {
       # On desktop platforms these don't take very long (~7 minutes),