Multiple FYI GPU bots are having errors:

https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac%20FYI%20Experimental%20Release%20%28Intel%29/2089
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Win10%20FYI%20Release%20%28NVIDIA%29/1026
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Win7%20FYI%20x64%20Release%20%28NVIDIA%29/952
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac%20FYI%20Experimental%20Release%20%28Intel%29/2089
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac%20FYI%20Retina%20Debug%20%28NVIDIA%29/1495
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac%20FYI%20Retina%20Release%20%28NVIDIA%29/1335
https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac%20FYI%20GPU%20ASAN%20Release/801

In each case, webgl2_conformance_tests are failing on a different test across a range of devices:


[111/138] gpu_tests.webgl_conformance_integration_test.WebGLConformanceIntegrationTest.WebglConformance_deqp_functional_gles3_shadermatrix_add_assign failed unexpectedly 618.6246s:

[133/139] gpu_tests.webgl_conformance_integration_test.WebGLConformanceIntegrationTest.WebglConformance_deqp_functional_gles3_texturespecification_basic_teximage3d_2d_array_02 failed unexpectedly 322.8495s:
  
[424/462] gpu_tests.webgl_conformance_integration_test.WebGLConformanceIntegrationTest.WebglConformance_conformance_more_conformance_constants failed unexpectedly 324.2782s:

[60/136] gpu_tests.webgl_conformance_integration_test.WebGLConformanceIntegrationTest.WebglConformance_conformance_glsl_functions_glsl_function_clamp_float failed unexpectedly 317.1177s:
 
[113/140] gpu_tests.webgl_conformance_integration_test.WebGLConformanceIntegrationTest.WebglConformance_deqp_functional_gles3_shaderoperator_angle_and_trigonometry_03 failed unexpectedly 320.3420s:

[109/138] gpu_tests.webgl_conformance_integration_test.WebGLConformanceIntegrationTest.WebglConformance_deqp_functional_gles3_shadermatrix_add_const failed unexpectedly 317.7220s:
 
[60/136] gpu_tests.webgl_conformance_integration_test.WebGLConformanceIntegrationTest.WebglConformance_conformance_glsl_functions_glsl_function_clamp_float failed unexpectedly 317.1177s:


Each such failure looks like this:
  Traceback (most recent call last):
    _RunGpuTest at content/test/gpu/gpu_tests/gpu_integration_test.py:132
      self.RunActualGpuTest(url, *args)
    RunActualGpuTest at content/test/gpu/gpu_tests/webgl_conformance_integration_test.py:188
      getattr(self, test_name)(test_path, *args[1:])
    _RunConformanceTest at content/test/gpu/gpu_tests/webgl_conformance_integration_test.py:202
      self._CheckTestCompletion()
    _CheckTestCompletion at content/test/gpu/gpu_tests/webgl_conformance_integration_test.py:196
      'webglTestHarness._finished', timeout=self._GetTestTimeout())
    traced_function at third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py:52
      return func(*args, **kwargs)
    WaitForJavaScriptCondition at third_party/catapult/telemetry/telemetry/internal/actions/action_runner.py:261
      return self._tab.WaitForJavaScriptCondition(*args, **kwargs)
    traced_function at third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py:52
      return func(*args, **kwargs)
    WaitForJavaScriptCondition at third_party/catapult/telemetry/telemetry/internal/browser/web_contents.py:239
      return self._inspector_backend.WaitForJavaScriptCondition(*args, **kwargs)
    traced_function at third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py:52
      return func(*args, **kwargs)
    WaitForJavaScriptCondition at third_party/catapult/telemetry/telemetry/internal/backends/chrome_inspector/inspector_backend.py:302
      e.message + '\n' + debug_message)
  TimeoutException: Timed out while waiting 300s for IsJavaScriptExpressionTrue.
  Console output:
  
  Locals:
    IsJavaScriptExpressionTrue : <function IsJavaScriptExpressionTrue at 0x105997cf8>
    condition                  : 'webglTestHarness._finished'
    context_id                 : None
    debug_message              : 'Console output:\n'
    e                          : TimeoutException('Timed out while waiting 300s for IsJavaScriptExpressionTrue.',)
    kwargs                     : {}
    timeout                    : 300
  
  Found crashpad_database_util
  No minidump found via crashpad_database_util
  No minidump paths to symbolize
  Found crashpad_database_util
  No minidump found via crashpad_database_util
  Restarting browser due to unexpected test failure
  Closing browser (pid=8299) ...
  Browser is closed.
  Starting Chrome ['/b/s/w/ir/out/Release/Chromium.app/Contents/MacOS/Chromium', '--disable-gpu-watchdog', '--enable-experimental-web-platform-features', '--test-type=gpu', '--disable-domain-blocking-for-3d-apis', '--disable-gpu-process-crash-limit', '--disable-blink-features=WebXR', '--js-flags=--expose-gc', '--enable-logging=stderr', '--autoplay-policy=no-user-gesture-required', '--use-cmd-decoder=validating', '--enable-net-benchmarking', '--metrics-recording-only', '--no-default-browser-check', '--no-first-run', '--enable-gpu-benchmarking', '--deny-permission-prompts', '--autoplay-policy=no-user-gesture-required', '--disable-background-networking', '--disable-component-extensions-with-background-pages', '--disable-default-apps', '--disable-search-geolocation-disclosure', '--proxy-server=socks://localhost:53758', '--ignore-certificate-errors-spki-list=PhrPvGIaAMmd29hj8BCZOq096yj7uMpRNHpn5PDxI6I=', '--remote-debugging-port=0', '--enable-crash-reporter-for-testing', '--disable-component-update', '--window-size=1280,1024', '--user-data-dir=/b/s/w/itZPMhfX/tmpqw7awd', 'about:blank']
  DoNothingForwarder started between 127.0.0.1:53901 and 53901
  Got devtools config: ws://127.0.0.1:53901/devtools/browser/90db85be-1408-40ba-aa82-a1bde1b5e56f
  Browser started (pid=8379).
  OS: mac highsierra
  Detailed OS version: 10.13.4 17E139j
  Model: Macmini 7.1
  Browser command line: /b/s/w/ir/out/Release/Chromium.app/Contents/MacOS/Chromium --disable-gpu-watchdog --enable-experimental-web-platform-features --test-type=gpu --disable-domain-blocking-for-3d-apis --disable-gpu-process-crash-limit --disable-blink-features=WebXR --js-flags=--expose-gc --enable-logging=stderr --autoplay-policy=no-user-gesture-required --use-cmd-decoder=validating --enable-net-benchmarking --metrics-recording-only --no-default-browser-check --no-first-run --enable-gpu-benchmarking --deny-permission-prompts --autoplay-policy=no-user-gesture-required --disable-background-networking --disable-component-extensions-with-background-pages --disable-default-apps --disable-search-geolocation-disclosure --proxy-server=socks://localhost:53758 --ignore-certificate-errors-spki-list=PhrPvGIaAMmd29hj8BCZOq096yj7uMpRNHpn5PDxI6I= --remote-debugging-port=0 --enable-crash-reporter-for-testing --disable-component-update --window-size=1280,1024 --user-data-dir=/b/s/w/itZPMhfX/tmpqw7awd --flag-switches-begin --flag-switches-end about:blank
  GPU device 0: VENDOR = 0x8086 (Intel), DEVICE = 0xa2e
  GPU Attributes:
    amd_switchable      : False
    can_support_threaded_texture_mailbox: False
    direct_composition  : False
    direct_rendering    : True
    driver_date         : 
    driver_vendor       : 
    driver_version      : 
    encrypted_only      : False
    gl_extensions       : 
    gl_renderer         : 
    gl_reset_notification_strategy: 0
    gl_vendor           : 
    gl_version          : 
    gl_ws_extensions    : 
    gl_ws_vendor        : 
    gl_ws_version       : 
    in_process_gpu      : False
    initialization_time : 0.0902
    jpeg_decode_accelerator_supported: False
    max_framerate_denominator: 1
    max_framerate_numerator: 30
    max_msaa_samples    : 
    max_resolution_height: 2160
    max_resolution_width: 4096
    min_resolution_height: 16
    min_resolution_width: 16
    optimus             : False
    passthrough_cmd_decoder: False
    pixel_shader_version: 
    process_crash_count : 0
    profile             : 3
    sandboxed           : True
    software_rendering  : False
    supports_overlays   : False
    vertex_shader_version: 
    video_decode_accelerator_flags: 0
  Feature Status:
    2d_canvas           : enabled
    flash_3d            : enabled
    flash_stage3d       : enabled
    flash_stage3d_baseline: enabled
    gpu_compositing     : enabled
    multiple_raster_threads: enabled_on
    native_gpu_memory_buffers: enabled
    rasterization       : enabled
    surface_synchronization: enabled_on
    video_decode        : enabled
    viz_display_compositor: disabled_off
    webgl               : enabled
    webgl2              : enabled
  Driver Bug Workarounds:
    add_and_true_to_loop_condition
    adjust_src_dst_region_for_blitframebuffer
    avoid_stencil_buffers
    decode_encode_srgb_for_generatemipmap
    disable_framebuffer_cmaa
    disable_webgl_rgb_multisampling_usage
    dont_use_loops_to_initialize_variables
    emulate_abs_int_function
    get_frag_data_info_bug
    init_two_cube_map_levels_before_copyteximage
    max_msaa_sample_count_4
    msaa_is_slow
    pack_parameters_workaround_with_pack_buffer
    rebind_transform_feedback_before_resume
    regenerate_struct_names
    remove_invariant_and_centroid_for_essl3
    reset_teximage2d_base_level
    rewrite_texelfetchoffset_to_texelfetch
    scalarize_vec_and_mat_constructor_args
    set_zero_level_before_generating_mipmap
    unfold_short_circuit_as_ternary_operation
    unpack_alignment_workaround_with_unpack_buffer
    unpack_image_height_workaround_with_unpack_buffer
    use_intermediary_for_copy_texture_image
    use_unused_standard_shared_blocks
  Traceback (most recent call last):
    File "/b/s/w/ir/third_party/catapult/telemetry/telemetry/testing/serially_executed_browser_test_case.py", line 206, in <lambda>
      return lambda self: based_method(self, *args)
    File "/b/s/w/ir/content/test/gpu/gpu_tests/gpu_integration_test.py", line 132, in _RunGpuTest
      self.RunActualGpuTest(url, *args)
    File "/b/s/w/ir/content/test/gpu/gpu_tests/webgl_conformance_integration_test.py", line 188, in RunActualGpuTest
      getattr(self, test_name)(test_path, *args[1:])
    File "/b/s/w/ir/content/test/gpu/gpu_tests/webgl_conformance_integration_test.py", line 202, in _RunConformanceTest
      self._CheckTestCompletion()
    File "/b/s/w/ir/content/test/gpu/gpu_tests/webgl_conformance_integration_test.py", line 196, in _CheckTestCompletion
      'webglTestHarness._finished', timeout=self._GetTestTimeout())
    File "/b/s/w/ir/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 52, in traced_function
      return func(*args, **kwargs)
    File "/b/s/w/ir/third_party/catapult/telemetry/telemetry/internal/actions/action_runner.py", line 261, in WaitForJavaScriptCondition
      return self._tab.WaitForJavaScriptCondition(*args, **kwargs)
    File "/b/s/w/ir/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 52, in traced_function
      return func(*args, **kwargs)
    File "/b/s/w/ir/third_party/catapult/telemetry/telemetry/internal/browser/web_contents.py", line 239, in WaitForJavaScriptCondition
      return self._inspector_backend.WaitForJavaScriptCondition(*args, **kwargs)
    File "/b/s/w/ir/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 52, in traced_function
      return func(*args, **kwargs)
    File "/b/s/w/ir/third_party/catapult/telemetry/telemetry/internal/backends/chrome_inspector/inspector_backend.py", line 302, in WaitForJavaScriptCondition
      e.message + '\n' + debug_message)
  TimeoutException: Timed out while waiting 300s for IsJavaScriptExpressionTrue.
  Console output:
  
[8379:775:0508/111601.508531:WARNING:gaia_auth_fetcher.cc(902)] Could not reach Google Accounts servers: errno -120

A catapult issue perhaps? Suggestions welcome.