Started here
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%2010.10%20Release%20%28ATI%29/builds/12549

More appearances:
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%2010.10%20Release%20%28ATI%29/builds/12564
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%2010.10%20Release%20%28ATI%29/builds/12551
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%2010.10%20Release%20%28ATI%29/builds/12550

And also on Intel
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%2010.10%20Release%20%28Intel%29/builds/18624
https://build.chromium.org/p/chromium.gpu.fyi/builders/Mac%2010.10%20Release%20%28Intel%29/builds/18615

Log:
Pixel_ScissorTestWithPreserveDrawingBuffer (gpu_tests.pixel_integration_test.PixelIntegrationTest) ... (WARNING) 2016-10-28 09:46:47,728 pixel_integration_test.RestartBrowserIfNecessaryWithArgs:92  Restarting browser with arguments: []
[7057:39683:1028/094647:ERROR:ssl_client_socket_impl.cc(1081)] handshake failed; returned -1, SSL error code 1, net_error -100
[7057:39683:1028/094647:ERROR:ssl_client_socket_impl.cc(1081)] handshake failed; returned -1, SSL error code 1, net_error -100
[7057:39683:1028/094647:ERROR:ssl_client_socket_impl.cc(1081)] handshake failed; returned -1, SSL error code 1, net_error -100
[7057:39683:1028/094647:ERROR:ssl_client_socket_impl.cc(1081)] handshake failed; returned -1, SSL error code 1, net_error -100
(WARNING) 2016-10-28 09:46:53,677 desktop_browser_backend.Close:598  Failed to gracefully shutdown.
(WARNING) 2016-10-28 09:46:53,678 desktop_browser_backend.Close:602  Proceed to kill the browser.
(WARNING) 2016-10-28 09:46:53,947 desktop_browser_finder.FindAllAvailableBrowsers:147  Chrome build location for mac_x86_64 not found. Browser will be run without Flash.
(INFO) 2016-10-28 09:46:53,948 browser_finder.FindBrowser:123  Chose browser: PossibleDesktopBrowser(type=release, executable=/b/c/b/Mac_10_10_Release__ATI_/irvPX2G0/out/Release/Chromium.app/Contents/MacOS/Chromium, flash=None)
(WARNING) 2016-10-28 09:46:53,949 gpu_integration_test.StartBrowser:38  Starting browser, attempt 1 of 3
(INFO) 2016-10-28 09:46:53,950 desktop_browser_backend.GetBrowserStartupArgs:250  Requested remote debugging port: 0
(INFO) 2016-10-28 09:46:53,950 desktop_browser_backend.Start:285  Starting Chrome ['/b/c/b/Mac_10_10_Release__ATI_/irvPX2G0/out/Release/Chromium.app/Contents/MacOS/Chromium', '--test-type=gpu', '--js-flags=--expose-gc', '--enable-logging=stderr', '--enable-gpu-benchmarking', '--enable-net-benchmarking', '--metrics-recording-only', '--no-default-browser-check', '--no-first-run', '--enable-gpu-benchmarking', '--disable-background-networking', '--proxy-server=socks://localhost:50129', '--ignore-certificate-errors', '--disable-component-extensions-with-background-pages', '--disable-default-apps', '--remote-debugging-port=0', '--enable-crash-reporter-for-testing', '--window-size=1280,1024', '--user-data-dir=/b/c/b/Mac_10_10_Release__ATI_/itilT6jS/tmpOOkDAE', 'about:blank']
2016-10-28 09:46:54.245 Chromium[7098:38982] NSWindow warning: adding an unknown subview: <FullSizeContentView: 0x7f8e44b7f700>
2016-10-28 09:46:54.245 Chromium[7098:38982] Call stack:
(
    "+callStackSymbols disabled for performance reasons"
)
(INFO) 2016-10-28 09:46:54,270 desktop_browser_backend.HasBrowserFinishedLaunching:237  Discovered ephemeral port 51306
[7098:39939:1028/094654:ERROR:ssl_client_socket_impl.cc(1081)] handshake failed; returned -1, SSL error code 1, net_error -100
[7098:39939:1028/094654:ERROR:ssl_client_socket_impl.cc(1081)] handshake failed; returned -1, SSL error code 1, net_error -100
[09:46:54.352] vtDecompressionDuctCreate signalled err=-8973 (err) (Could not select and open decoder instance) at /SourceCache/CoreMedia_frameworks/CoreMedia-1562.238/Sources/VideoToolbox/VTDecompressionSession.c line 1181
[7105:1299:1028/094654:WARNING:vt_video_decode_accelerator_mac.cc(174)] Failed to create VTDecompressionSession: Error Domain=NSOSStatusErrorDomain Code=-8973 "The operation couldn’t be completed. (OSStatus error -8973.)" (codecOpenErr) (-8973)
[7105:1299:1028/094654:WARNING:vt_video_decode_accelerator_mac.cc(209)] Failed to create hardware VideoToolbox session
[09:46:54.412] VTCompressionSessionCreate signalled err=-8973 (err) (VTVideoEncoderStartSession failed) at /SourceCache/CoreMedia_frameworks/CoreMedia-1562.238/Sources/VideoToolbox/VTCompressionSession.c line 967
<<<< VTVideoEncoderSelection >>>> VTSelectAndCreateVideoEncoderInstanceInternal: no video encoder accepted for 'avc1'

[09:46:54.412] VTSelectAndCreateVideoEncoderInstanceInternal signalled err=-12908 (err) (Video encoder not accepted) at /SourceCache/CoreMedia_frameworks/CoreMedia-1562.238/Sources/VideoToolbox/VTVideoEncoderSelection.c line 1241
[09:46:54.412] VTCompressionSessionCreate signalled err=-8973 (err) (Could not select and open encoder instance) at /SourceCache/CoreMedia_frameworks/CoreMedia-1562.238/Sources/VideoToolbox/VTCompressionSession.c line 946
[7105:1299:1028/094654:ERROR:vt_video_encode_accelerator_mac.cc(540)]  VTCompressionSessionCreate failed: -8973
(INFO) 2016-10-28 09:46:54,635 browser._LogBrowserInfo:113  OS: mac yosemite
(INFO) 2016-10-28 09:46:54,646 browser._LogBrowserInfo:117  Model: MacPro
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:120  GPU device 0: VENDOR = 0x1002 (ATI), DEVICE = 0x679e
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:120  GPU device 1: VENDOR = 0x1002 (ATI), DEVICE = 0x679e
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:122  GPU Attributes:
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:124    adapter_luid        : 0.0
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:124    amd_switchable      : False
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:124    basic_info_state    : 1
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:124    context_info_state  : 1
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:124    direct_rendering    : True
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:124    driver_date         : 
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:124    driver_vendor       : 
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:124    driver_version      : 1.32.25
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:124    encrypted_only      : False
(INFO) 2016-10-28 09:46:54,647 browser._LogBrowserInfo:124    gl_extensions       : GL_ARB_blend_func_extended GL_ARB_draw_buffers_blend GL_ARB_draw_indirect GL_ARB_ES2_compatibility GL_ARB_explicit_attrib_location GL_ARB_gpu_shader_fp64 GL_ARB_gpu_shader5 GL_ARB_instanced_arrays GL_ARB_internalformat_query GL_ARB_occlusion_query2 GL_ARB_sample_shading GL_ARB_sampler_objects GL_ARB_separate_shader_objects GL_ARB_shader_bit_encoding GL_ARB_shader_subroutine GL_ARB_shading_language_include GL_ARB_tessellation_shader GL_ARB_texture_buffer_object_rgb32 GL_ARB_texture_cube_map_array GL_ARB_texture_gather GL_ARB_texture_query_lod GL_ARB_texture_rgb10_a2ui GL_ARB_texture_storage GL_ARB_texture_swizzle GL_ARB_timer_query GL_ARB_transform_feedback2 GL_ARB_transform_feedback3 GL_ARB_vertex_attrib_64bit GL_ARB_vertex_type_2_10_10_10_rev GL_ARB_viewport_array GL_EXT_debug_label GL_EXT_debug_marker GL_EXT_depth_bounds_test GL_EXT_texture_compression_s3tc GL_EXT_texture_filter_anisotropic GL_EXT_texture_mirror_clamp GL_EXT_texture_sRGB_decode GL_APPLE_client_storage GL_APPLE_container_object_shareable GL_APPLE_flush_render GL_APPLE_object_purgeable GL_APPLE_rgb_422 GL_APPLE_row_bytes GL_APPLE_texture_range GL_ATI_texture_mirror_once GL_NV_texture_barrier
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    gl_renderer         : AMD Radeon HD - FirePro D500 OpenGL Engine
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    gl_reset_notification_strategy: 0
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    gl_vendor           : ATI Technologies Inc.
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    gl_version          : 4.1 ATI-1.32.25
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    gl_ws_extensions    : 
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    gl_ws_vendor        : 
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    gl_ws_version       : 
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    in_process_gpu      : False
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    initialization_time : 0.007092
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    jpeg_decode_accelerator_supported: False
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    lenovo_dcute        : False
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    max_msaa_samples    : 8
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    max_resolution_height: 2160
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    max_resolution_width: 4096
(INFO) 2016-10-28 09:46:54,648 browser._LogBrowserInfo:124    min_resolution_height: 16
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:124    min_resolution_width: 16
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:124    optimus             : False
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:124    pixel_shader_version: 4.10
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:124    process_crash_count : 0
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:124    profile             : 3
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:124    sandboxed           : True
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:124    software_rendering  : False
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:124    vertex_shader_version: 4.10
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:124    video_decode_accelerator_flags: 0
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:126  Feature Status:
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:128    2d_canvas           : enabled
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:128    flash_3d            : enabled
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:128    flash_stage3d       : enabled
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:128    flash_stage3d_baseline: enabled
(INFO) 2016-10-28 09:46:54,649 browser._LogBrowserInfo:128    gpu_compositing     : enabled
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:128    multiple_raster_threads: enabled_on
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:128    native_gpu_memory_buffers: enabled
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:128    rasterization       : enabled
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:128    video_decode        : enabled
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:128    video_encode        : enabled
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:128    vpx_decode          : enabled
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:128    webgl               : enabled
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:130  Driver Bug Workarounds:
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:132    adjust_src_dst_region_for_blitframebuffer
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:132    decode_encode_srgb_for_generatemipmap
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:132    disable_av_sample_buffer_display_layer
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:132    disable_framebuffer_cmaa
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:132    disable_multimonitor_multisampling
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:132    get_frag_data_info_bug
(INFO) 2016-10-28 09:46:54,650 browser._LogBrowserInfo:132    pack_parameters_workaround_with_pack_buffer
(INFO) 2016-10-28 09:46:54,651 browser._LogBrowserInfo:132    regenerate_struct_names
(INFO) 2016-10-28 09:46:54,651 browser._LogBrowserInfo:132    rewrite_do_while_loops
(INFO) 2016-10-28 09:46:54,651 browser._LogBrowserInfo:132    scalarize_vec_and_mat_constructor_args
(INFO) 2016-10-28 09:46:54,651 browser._LogBrowserInfo:132    set_zero_level_before_generating_mipmap
(INFO) 2016-10-28 09:46:54,651 browser._LogBrowserInfo:132    unfold_short_circuit_as_ternary_operation
(INFO) 2016-10-28 09:46:54,651 browser._LogBrowserInfo:132    unpack_alignment_workaround_with_unpack_buffer
(INFO) 2016-10-28 09:46:54,651 browser._LogBrowserInfo:132    use_intermediary_for_copy_texture_image
(INFO) 2016-10-28 09:46:54,651 browser._LogBrowserInfo:132    use_shadowed_tex_level_params
(INFO) 2016-10-28 09:46:54,651 browser._LogBrowserInfo:132    use_unused_standard_shared_blocks
[7098:60931:1028/094654:WARNING:simple_synchronous_entry.cc(1054)] Could not open platform files for entry.
(INFO) 2016-10-28 09:46:57,029 cloud_storage.Insert:310  Uploading /b/c/b/Mac_10_10_Release__ATI_/itilT6jS/tmpdPKQYo.png to gs://chromium-browser-gpu-tests/runs/eb5958ae41b8c4b4a415a1efe0f1eb9a30fd0530_Mac_10_10_Release_ATI__telemetry/gen/Pixel_ScissorTestWithPreserveDrawingBuffer_eb5958ae41b8c4b4a415a1efe0f1eb9a30fd0530.png (publicly readable)
See http://chromium-browser-gpu-tests.commondatastorage.googleapis.com/view_test_results.html?eb5958ae41b8c4b4a415a1efe0f1eb9a30fd0530_Mac_10_10_Release_ATI__telemetry for this run's test results

Traceback (most recent call last):
  _RunGpuTest at content/test/gpu/gpu_tests/gpu_integration_test.py:78
    self.RunActualGpuTest(url, *args)
  RunActualGpuTest at content/test/gpu/gpu_tests/pixel_integration_test.py:160
    tab, page.name, screenshot, page.expected_colors, dpr)
  _ValidateScreenshotSamples at content/test/gpu/gpu_tests/cloud_storage_integration_test_base.py:352
    self.GetParsedCommandLineOptions().test_machine_name)
  _CompareScreenshotSamples at content/test/gpu/gpu_tests/cloud_storage_integration_test_base.py:165
    str(actual_color.b) + "]")
  fail at /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/unittest/case.py:412
    raise self.failureException(msg)
AssertionError: Expected pixel at [1, 1] (actual pixel (1, 1))  to be [255, 0, 0] but got [255, 255, 255]

Locals:
  msg : 'Expected pixel at [1, 1] (actual pixel (1, 1))  to be [255, 0, 0] but got [255, 255, 255]'

(WARNING) 2016-10-28 09:46:57,878 gpu_integration_test._RestartBrowser:56  Restarting browser due to unexpected test failure
(WARNING) 2016-10-28 09:47:03,866 desktop_browser_backend.Close:598  Failed to gracefully shutdown.
(WARNING) 2016-10-28 09:47:03,866 desktop_browser_backend.Close:602  Proceed to kill the browser.
(WARNING) 2016-10-28 09:47:03,871 gpu_integration_test.StartBrowser:38  Starting browser, attempt 1 of 3
(INFO) 2016-10-28 09:47:03,872 desktop_browser_backend.GetBrowserStartupArgs:250  Requested remote debugging port: 0
(INFO) 2016-10-28 09:47:03,872 desktop_browser_backend.Start:285  Starting Chrome ['/b/c/b/Mac_10_10_Release__ATI_/irvPX2G0/out/Release/Chromium.app/Contents/MacOS/Chromium', '--test-type=gpu', '--js-flags=--expose-gc', '--enable-logging=stderr', '--enable-gpu-benchmarking', '--enable-net-benchmarking', '--metrics-recording-only', '--no-default-browser-check', '--no-first-run', '--enable-gpu-benchmarking', '--disable-background-networking', '--proxy-server=socks://localhost:50129', '--ignore-certificate-errors', '--disable-component-extensions-with-background-pages', '--disable-default-apps', '--remote-debugging-port=0', '--enable-crash-reporter-for-testing', '--window-size=1280,1024', '--user-data-dir=/b/c/b/Mac_10_10_Release__ATI_/itilT6jS/tmpD1V2NH', 'about:blank']
2016-10-28 09:47:04.151 Chromium[7119:39317] NSWindow warning: adding an unknown subview: <FullSizeContentView: 0x7fd55cd14f90>
2016-10-28 09:47:04.151 Chromium[7119:39317] Call stack:
(
    "+callStackSymbols disabled for performance reasons"
)
(INFO) 2016-10-28 09:47:04,193 desktop_browser_backend.HasBrowserFinishedLaunching:237  Discovered ephemeral port 51334
[7119:41219:1028/094704:ERROR:ssl_client_socket_impl.cc(1081)] handshake failed; returned -1, SSL error code 1, net_error -100
[7119:41219:1028/094704:ERROR:ssl_client_socket_impl.cc(1081)] handshake failed; returned -1, SSL error code 1, net_error -100
[09:47:04.257] vtDecompressionDuctCreate signalled err=-8973 (err) (Could not select and open decoder instance) at /SourceCache/CoreMedia_frameworks/CoreMedia-1562.238/Sources/VideoToolbox/VTDecompressionSession.c line 1181
[7122:1299:1028/094704:WARNING:vt_video_decode_accelerator_mac.cc(174)] Failed to create VTDecompressionSession: Error Domain=NSOSStatusErrorDomain Code=-8973 "The operation couldn’t be completed. (OSStatus error -8973.)" (codecOpenErr) (-8973)
[7122:1299:1028/094704:WARNING:vt_video_decode_accelerator_mac.cc(209)] Failed to create hardware VideoToolbox session
[09:47:04.319] VTCompressionSessionCreate signalled err=-8973 (err) (VTVideoEncoderStartSession failed) at /SourceCache/CoreMedia_frameworks/CoreMedia-1562.238/Sources/VideoToolbox/VTCompressionSession.c line 967
<<<< VTVideoEncoderSelection >>>> VTSelectAndCreateVideoEncoderInstanceInternal: no video encoder accepted for 'avc1'

[09:47:04.319] VTSelectAndCreateVideoEncoderInstanceInternal signalled err=-12908 (err) (Video encoder not accepted) at /SourceCache/CoreMedia_frameworks/CoreMedia-1562.238/Sources/VideoToolbox/VTVideoEncoderSelection.c line 1241
[09:47:04.319] VTCompressionSessionCreate signalled err=-8973 (err) (Could not select and open encoder instance) at /SourceCache/CoreMedia_frameworks/CoreMedia-1562.238/Sources/VideoToolbox/VTCompressionSession.c line 946
[7122:1299:1028/094704:ERROR:vt_video_encode_accelerator_mac.cc(540)]  VTCompressionSessionCreate failed: -8973
(INFO) 2016-10-28 09:47:04,545 browser._LogBrowserInfo:113  OS: mac yosemite
(INFO) 2016-10-28 09:47:04,555 browser._LogBrowserInfo:117  Model: MacPro
(INFO) 2016-10-28 09:47:04,555 browser._LogBrowserInfo:120  GPU device 0: VENDOR = 0x1002 (ATI), DEVICE = 0x679e
(INFO) 2016-10-28 09:47:04,555 browser._LogBrowserInfo:120  GPU device 1: VENDOR = 0x1002 (ATI), DEVICE = 0x679e
(INFO) 2016-10-28 09:47:04,555 browser._LogBrowserInfo:122  GPU Attributes:
(INFO) 2016-10-28 09:47:04,555 browser._LogBrowserInfo:124    adapter_luid        : 0.0
(INFO) 2016-10-28 09:47:04,555 browser._LogBrowserInfo:124    amd_switchable      : False
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    basic_info_state    : 1
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    context_info_state  : 1
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    direct_rendering    : True
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    driver_date         : 
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    driver_vendor       : 
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    driver_version      : 1.32.25
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    encrypted_only      : False
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    gl_extensions       : GL_ARB_blend_func_extended GL_ARB_draw_buffers_blend GL_ARB_draw_indirect GL_ARB_ES2_compatibility GL_ARB_explicit_attrib_location GL_ARB_gpu_shader_fp64 GL_ARB_gpu_shader5 GL_ARB_instanced_arrays GL_ARB_internalformat_query GL_ARB_occlusion_query2 GL_ARB_sample_shading GL_ARB_sampler_objects GL_ARB_separate_shader_objects GL_ARB_shader_bit_encoding GL_ARB_shader_subroutine GL_ARB_shading_language_include GL_ARB_tessellation_shader GL_ARB_texture_buffer_object_rgb32 GL_ARB_texture_cube_map_array GL_ARB_texture_gather GL_ARB_texture_query_lod GL_ARB_texture_rgb10_a2ui GL_ARB_texture_storage GL_ARB_texture_swizzle GL_ARB_timer_query GL_ARB_transform_feedback2 GL_ARB_transform_feedback3 GL_ARB_vertex_attrib_64bit GL_ARB_vertex_type_2_10_10_10_rev GL_ARB_viewport_array GL_EXT_debug_label GL_EXT_debug_marker GL_EXT_depth_bounds_test GL_EXT_texture_compression_s3tc GL_EXT_texture_filter_anisotropic GL_EXT_texture_mirror_clamp GL_EXT_texture_sRGB_decode GL_APPLE_client_storage GL_APPLE_container_object_shareable GL_APPLE_flush_render GL_APPLE_object_purgeable GL_APPLE_rgb_422 GL_APPLE_row_bytes GL_APPLE_texture_range GL_ATI_texture_mirror_once GL_NV_texture_barrier
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    gl_renderer         : AMD Radeon HD - FirePro D500 OpenGL Engine
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    gl_reset_notification_strategy: 0
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    gl_vendor           : ATI Technologies Inc.
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    gl_version          : 4.1 ATI-1.32.25
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    gl_ws_extensions    : 
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    gl_ws_vendor        : 
(INFO) 2016-10-28 09:47:04,556 browser._LogBrowserInfo:124    gl_ws_version       : 
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    in_process_gpu      : False
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    initialization_time : 0.007847
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    jpeg_decode_accelerator_supported: False
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    lenovo_dcute        : False
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    max_msaa_samples    : 8
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    max_resolution_height: 2160
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    max_resolution_width: 4096
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    min_resolution_height: 16
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    min_resolution_width: 16
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    optimus             : False
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    pixel_shader_version: 4.10
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    process_crash_count : 0
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    profile             : 3
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    sandboxed           : True
(INFO) 2016-10-28 09:47:04,557 browser._LogBrowserInfo:124    software_rendering  : False
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:124    vertex_shader_version: 4.10
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:124    video_decode_accelerator_flags: 0
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:126  Feature Status:
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    2d_canvas           : enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    flash_3d            : enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    flash_stage3d       : enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    flash_stage3d_baseline: enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    gpu_compositing     : enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    multiple_raster_threads: enabled_on
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    native_gpu_memory_buffers: enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    rasterization       : enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    video_decode        : enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    video_encode        : enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    vpx_decode          : enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:128    webgl               : enabled
(INFO) 2016-10-28 09:47:04,558 browser._LogBrowserInfo:130  Driver Bug Workarounds:
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    adjust_src_dst_region_for_blitframebuffer
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    decode_encode_srgb_for_generatemipmap
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    disable_av_sample_buffer_display_layer
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    disable_framebuffer_cmaa
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    disable_multimonitor_multisampling
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    get_frag_data_info_bug
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    pack_parameters_workaround_with_pack_buffer
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    regenerate_struct_names
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    rewrite_do_while_loops
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    scalarize_vec_and_mat_constructor_args
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    set_zero_level_before_generating_mipmap
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    unfold_short_circuit_as_ternary_operation
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    unpack_alignment_workaround_with_unpack_buffer
(INFO) 2016-10-28 09:47:04,559 browser._LogBrowserInfo:132    use_intermediary_for_copy_texture_image
(INFO) 2016-10-28 09:47:04,560 browser._LogBrowserInfo:132    use_shadowed_tex_level_params
(INFO) 2016-10-28 09:47:04,560 browser._LogBrowserInfo:132    use_unused_standard_shared_blocks
FAIL

This started happening around the same time that cc changes triggering  issue 660118  were made. ajuma@, could you check if this may be related?