Run the WebGL conformance tests with the passthrough command decoder.

content/test/gpu/generate_buildbot_json.py

Index: content/test/gpu/generate_buildbot_json.py
diff --git a/content/test/gpu/generate_buildbot_json.py b/content/test/gpu/generate_buildbot_json.py
index 9e51c1df7e36a7c933e74ee94ebd2fe86f55feca..3e6b0f6c3007295cd784cb5ea3813f5de7777216 100755
--- a/content/test/gpu/generate_buildbot_json.py
+++ b/content/test/gpu/generate_buildbot_json.py
@@ -1220,6 +1220,20 @@ TELEMETRY_GPU_INTEGRATION_TESTS = {
       '--use-gl=angle',
     ],
   },
+  'webgl_conformance_d3d11_passthrough': {
+    'tester_configs': [
+      {
+        'fyi_only': True,
+        'os_types': ['win'],
+        'run_on_optional': True,
+      }
+    ],
+    'target_name': 'webgl_conformance',
+    'extra_browser_args': [
+      '--use-angle=d3d11',
+      '--use-passthrough-cmd-decoder',
+    ],
+  },
   'webgl2_conformance_tests': {
     'tester_configs': [
       {