Log:
https://uberchromegw.corp.google.com/i/chromium.mac/builders/Mac10.11%20Tests/builds/2321/steps/telemetry_perf_unittests/logs/stdio

[275/277] core.minidump_unittest.BrowserMinidumpTest.testMultipleCrashMinidumps failed unexpectedly 6.6855s:
  Chrome build location for mac_x86_64 not found. Browser will be run without Flash.
  Requested remote debugging port: 0
  Starting Chrome ['/b/c/b/Mac10_11_Tests/irWKI7T0/out/Release/Chromium.app/Contents/MacOS/Chromium', '--enable-net-benchmarking', '--metrics-recording-only', '--no-default-browser-check', '--no-first-run', '--enable-gpu-benchmarking', '--disable-background-networking', '--no-proxy-server', '--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/Mac10_11_Tests/itb5PPuY/tmplUiyZ8', 'about:blank']
  Discovered ephemeral port 54518
  OS: mac elcapitan
  Model: Macmini
  GPU device 0: VENDOR = 0x8086 (Intel), DEVICE = 0xa2e
  GPU Attributes:
    adapter_luid        : 0.0
    amd_switchable      : False
    basic_info_state    : 1
    can_lose_context    : False
    context_info_state  : 1
    direct_rendering    : True
    driver_date         : 
    driver_vendor       : 
    driver_version      : 10.14.66
    encrypted_only      : False
    gl_extensions       : GL_ARB_color_buffer_float GL_ARB_depth_buffer_float GL_ARB_depth_clamp GL_ARB_depth_texture GL_ARB_draw_buffers GL_ARB_draw_elements_base_vertex GL_ARB_draw_instanced GL_ARB_fragment_program GL_ARB_fragment_program_shadow GL_ARB_fragment_shader GL_ARB_framebuffer_object GL_ARB_framebuffer_sRGB GL_ARB_half_float_pixel GL_ARB_half_float_vertex GL_ARB_instanced_arrays GL_ARB_multisample GL_ARB_multitexture GL_ARB_occlusion_query GL_ARB_pixel_buffer_object GL_ARB_point_parameters GL_ARB_point_sprite GL_ARB_provoking_vertex GL_ARB_seamless_cube_map GL_ARB_shader_objects GL_ARB_shader_texture_lod GL_ARB_shading_language_100 GL_ARB_shadow GL_ARB_sync GL_ARB_texture_border_clamp GL_ARB_texture_compression GL_ARB_texture_compression_rgtc GL_ARB_texture_cube_map GL_ARB_texture_env_add GL_ARB_texture_env_combine GL_ARB_texture_env_crossbar GL_ARB_texture_env_dot3 GL_ARB_texture_float GL_ARB_texture_mirrored_repeat GL_ARB_texture_non_power_of_two GL_ARB_texture_rectangle GL_ARB_texture_rg GL_ARB_transpose_matrix GL_ARB_vertex_array_bgra GL_ARB_vertex_blend GL_ARB_vertex_buffer_object GL_ARB_vertex_program GL_ARB_vertex_shader GL_ARB_window_pos GL_EXT_abgr GL_EXT_bgra GL_EXT_blend_color GL_EXT_blend_equation_separate GL_EXT_blend_func_separate GL_EXT_blend_minmax GL_EXT_blend_subtract GL_EXT_clip_volume_hint GL_EXT_debug_label GL_EXT_debug_marker GL_EXT_draw_buffers2 GL_EXT_draw_range_elements GL_EXT_fog_coord GL_EXT_framebuffer_blit GL_EXT_framebuffer_multisample GL_EXT_framebuffer_multisample_blit_scaled GL_EXT_framebuffer_object GL_EXT_framebuffer_sRGB GL_EXT_geometry_shader4 GL_EXT_gpu_program_parameters GL_EXT_gpu_shader4 GL_EXT_multi_draw_arrays GL_EXT_packed_depth_stencil GL_EXT_packed_float GL_EXT_provoking_vertex GL_EXT_rescale_normal GL_EXT_secondary_color GL_EXT_separate_specular_color GL_EXT_shadow_funcs GL_EXT_stencil_two_side GL_EXT_stencil_wrap GL_EXT_texture_array GL_EXT_texture_compression_dxt1 GL_EXT_texture_compression_s3tc GL_EXT_texture_env_add GL_EXT_texture_filter_anisotropic GL_EXT_texture_integer GL_EXT_texture_lod_bias GL_EXT_texture_rectangle GL_EXT_texture_shared_exponent GL_EXT_texture_sRGB GL_EXT_texture_sRGB_decode GL_EXT_timer_query GL_EXT_transform_feedback GL_EXT_vertex_array_bgra GL_APPLE_aux_depth_stencil GL_APPLE_client_storage GL_APPLE_element_array GL_APPLE_fence GL_APPLE_float_pixels GL_APPLE_flush_buffer_range GL_APPLE_flush_render GL_APPLE_object_purgeable GL_APPLE_packed_pixels GL_APPLE_pixel_buffer GL_APPLE_rgb_422 GL_APPLE_row_bytes GL_APPLE_specular_vector GL_APPLE_texture_range GL_APPLE_transform_hint GL_APPLE_vertex_array_object GL_APPLE_vertex_array_range GL_APPLE_vertex_point_size GL_APPLE_vertex_program_evaluators GL_APPLE_ycbcr_422 GL_ATI_separate_stencil GL_ATI_texture_env_combine3 GL_ATI_texture_float GL_ATI_texture_mirror_once GL_IBM_rasterpos_clip GL_NV_blend_square GL_NV_conditional_render GL_NV_depth_clamp GL_NV_fog_distance GL_NV_light_max_exponent GL_NV_texgen_reflection GL_NV_texture_barrier GL_SGIS_generate_mipmap GL_SGIS_texture_edge_clamp GL_SGIS_texture_lod 
    gl_renderer         : Intel Iris OpenGL Engine
    gl_reset_notification_strategy: 0
    gl_vendor           : Intel Inc.
    gl_version          : 2.1 INTEL-10.14.66
    gl_ws_extensions    : 
    gl_ws_vendor        : 
    gl_ws_version       : 
    in_process_gpu      : False
    initialization_time : 0.027312
    jpeg_decode_accelerator_supported: False
    lenovo_dcute        : False
    max_framerate_denominator: 1
    max_framerate_numerator: 30
    max_msaa_samples    : 8
    max_resolution_height: 2160
    max_resolution_width: 4096
    min_resolution_height: 16
    min_resolution_width: 16
    optimus             : False
    pixel_shader_version: 1.20
    process_crash_count : 0
    profile             : 0
    sandboxed           : True
    software_rendering  : False
    vertex_shader_version: 1.20
    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
    video_decode        : enabled
    video_encode        : enabled
    vpx_decode          : enabled
    webgl               : enabled
  Driver Bug Workarounds:
    disable_framebuffer_cmaa
    disable_multimonitor_multisampling
    disable_webgl_rgb_multisampling_usage
    msaa_is_slow
    pack_parameters_workaround_with_pack_buffer
    regenerate_struct_names
    scalarize_vec_and_mat_constructor_args
    set_zero_level_before_generating_mipmap
    unfold_short_circuit_as_ternary_operation
    unpack_alignment_workaround_with_unpack_buffer
    use_intermediary_for_copy_texture_image
    use_shadowed_tex_level_params
    validate_multisample_buffer_allocation
  Found crashpad_database_util
  No minidump found via crashpad_database_util
  *************** BROWSER STANDARD OUTPUT ***************
  2016-08-03 11:04:50.799 Chromium[6948:46506] NSWindow warning: adding an unknown subview: <FullSizeContentView: 0x7fb383fa1d30>. Break on NSLog to debug.
  2016-08-03 11:04:50.799 Chromium[6948:46506] Call stack:
  (
      "+callStackSymbols disabled for performance reasons"
  )
  Received signal 11 SEGV_MAPERR 000000000000
   [0x000106aa1cb6]
   [0x7fff9d33352a]
   [0x000000000000]
   [0x000109f862d2]
   [0x000109f852b4]
   [0x000108d18ffa]
   [0x000109f8682b]
   [0x000107a643eb]
   [0x000106aa22cb]
   [0x000106ac443c]
   [0x000106ac474c]
   [0x000106ac4af3]
   [0x000106ac6c6d]
   [0x000106aba6aa]
   [0x000106ac6674]
   [0x7fff9589c881]
   [0x7fff9587bfbc]
   [0x7fff9587b4df]
   [0x7fff9587aed8]
   [0x000106ac704f]
   [0x000106ac6ac4]
   [0x000106ae1b71]
   [0x000109f892e6]
   [0x00010665a8b0]
   [0x000106659a36]
   [0x0001051f13fa]
   [0x000104fb9d6a]
   [0x000104fb9b54]
  [end of stack trace]
  
  *********** END OF BROWSER STANDARD OUTPUT ************
  ********************* BROWSER LOG *********************
  No log file
  ***************** END OF BROWSER LOG ******************
  Traceback (most recent call last):
    File "/b/c/b/Mac10_11_Tests/irWKI7T0/third_party/catapult/telemetry/telemetry/testing/browser_test_case.py", line 41, in WrappedMethod
      method(self)
    File "/b/c/b/Mac10_11_Tests/irWKI7T0/third_party/catapult/telemetry/telemetry/decorators.py", line 163, in wrapper
      func(*args, **kwargs)
    File "/b/c/b/Mac10_11_Tests/irWKI7T0/tools/perf/core/minidump_unittest.py", line 52, in testMultipleCrashMinidumps
      + first_crash_path)
  TypeError: cannot concatenate 'str' and 'NoneType' objects
[0803/110527:WARNING:crash_report_database_mac.mm(636)] Failed to read report metadata for /b/c/b/Mac10_11_Tests/itb5PPuY/tmpaywGQu/completed/8cf0fd2e-0be5-40d4-bc72-cbe63ae3fb68.dmp.stripped