Seeing strange failures of entire Telemetry-based test suites on this optional GPU tryserver:
https://build.chromium.org/p/tryserver.chromium.android/builders/android_optional_gpu_tests_rel?numbuilds=200

In https://build.chromium.org/p/tryserver.chromium.android/builders/android_optional_gpu_tests_rel/builds/1287 , all of the context_lost_tests failed. It looked like the browser failed to start every time on the bot:

GpuCrash_GPUProcessCrashesExactlyOncePerVisitToAboutGpuCrash (gpu_tests.context_lost_integration_test.ContextLostIntegrationTest) ... (ERROR) 2016-12-07 18:44:42,115 gpu_integration_test._EnsureTabIsAvailable:196 Failure during browser startup
Traceback (most recent call last):
File "/b/swarm_slave/w/irKcgKuP/content/test/gpu/gpu_tests/gpu_integration_test.py", line 192, in _EnsureTabIsAvailable
cls.tab = cls.browser.tabs[0]
File "/b/swarm_slave/w/irKcgKuP/third_party/catapult/telemetry/telemetry/internal/browser/tab_list.py", line 18, in __getitem__
return self._tab_list_backend.__getitem__(index)
File "/b/swarm_slave/w/irKcgKuP/third_party/catapult/telemetry/telemetry/internal/backends/chrome_inspector/inspector_backend_list.py", line 64, in __getitem__
return self.GetBackendFromContextId(context_id)
File "/b/swarm_slave/w/irKcgKuP/third_party/catapult/telemetry/telemetry/internal/backends/chrome_inspector/inspector_backend_list.py", line 71, in GetBackendFromContextId
self._Update()
File "/b/swarm_slave/w/irKcgKuP/third_party/catapult/telemetry/telemetry/internal/backends/chrome_inspector/inspector_backend_list.py", line 99, in _Update
backends_map = self._devtools_client.GetUpdatedInspectableContexts()
File "/b/swarm_slave/w/irKcgKuP/third_party/catapult/telemetry/telemetry/internal/backends/chrome_inspector/devtools_client_backend.py", line 298, in GetUpdatedInspectableContexts
contexts = self._ListInspectableContexts()
File "/b/swarm_slave/w/irKcgKuP/third_party/catapult/telemetry/telemetry/internal/backends/chrome_inspector/devtools_client_backend.py", line 223, in _ListInspectableContexts
return self._devtools_http.RequestJson('')
File "/b/swarm_slave/w/irKcgKuP/third_party/catapult/telemetry/telemetry/internal/backends/chrome_inspector/devtools_http.py", line 107, in RequestJson
return json.loads(self.Request(path, timeout))
File "/b/swarm_slave/w/irKcgKuP/third_party/catapult/telemetry/telemetry/internal/backends/chrome_inspector/devtools_http.py", line 88, in Request
response = self._conn.getresponse()
File "/usr/lib/python2.7/httplib.py", line 1051, in getresponse
response.begin()
File "/usr/lib/python2.7/httplib.py", line 415, in begin
version, status, reason = self._read_status()
File "/usr/lib/python2.7/httplib.py", line 371, in _read_status
line = self.fp.readline(_MAXLINE + 1)
File "/usr/lib/python2.7/socket.py", line 476, in readline
data = self._sock.recv(self._rbufsize)
DevToolsClientConnectionError: timed out
(WARNING) 2016-12-07 18:44:42,115 gpu_integration_test._RestartBrowser:56 Restarting browser due to failure in setup
(INFO) 2016-12-07 18:44:42,116 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( ps | grep -F org.chromium.chrome; echo "PIPESTATUS: ${PIPESTATUS[@]}" );echo %$?'
(INFO) 2016-12-07 18:44:42,248 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( ls /root );echo %$?'
(INFO) 2016-12-07 18:44:42,349 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( cd /sys/devices/system/cpu && for CPU in cpu0 cpu1 cpu2 cpu3 cpu4 cpu5; do test -e "$CPU/cpufreq/scaling_governor" && echo ondemand > "$CPU/cpufreq/scaling_governor"; echo -n "%~%$?%~%"; done );echo %$?'
(INFO) 2016-12-07 18:44:42,412 perf_control._WriteEachCpuFile:116 Successfully set cpufreq/scaling_governor to 'ondemand' on: cpu0 cpu1 cpu2 cpu3 cpu4 cpu5
(INFO) 2016-12-07 18:44:42,413 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( cd /sys/devices/system/cpu && for CPU in cpu0 cpu1 cpu2 cpu3 cpu4 cpu5; do cat "$CPU/online"; echo -n "%~%$?%~%"; done );echo %$?'
(INFO) 2016-12-07 18:44:42,519 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( p=org.chromium.chrome;if [[ "$(ps)" = *$p* ]]; then am force-stop $p; fi );echo %$?'
(INFO) 2016-12-07 18:44:43,584 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af forward --remove tcp:39492
(WARNING) 2016-12-07 18:44:43,587 gpu_integration_test.StartBrowser:38 Starting browser, attempt 1 of 3
(INFO) 2016-12-07 18:44:43,588 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( p=org.chromium.chrome;if [[ "$(ps)" = *$p* ]]; then am force-stop $p; fi );echo %$?'
(INFO) 2016-12-07 18:44:43,688 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( ls /root );echo %$?'
(INFO) 2016-12-07 18:44:43,789 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( test -e /data/data/org.chromium.chrome/ );echo %$?'
(INFO) 2016-12-07 18:44:43,853 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( TZ=utc ls -a -l /data/data/org.chromium.chrome/ );echo %$?'
(INFO) 2016-12-07 18:44:43,953 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( rm -r /data/data/org.chromium.chrome/app_chrome /data/data/org.chromium.chrome/app_tabs /data/data/org.chromium.chrome/app_textures /data/data/org.chromium.chrome/cache /data/data/org.chromium.chrome/code_cache /data/data/org.chromium.chrome/files /data/data/org.chromium.chrome/shared_prefs );echo %$?'
(INFO) 2016-12-07 18:44:44,054 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af root
(INFO) 2016-12-07 18:44:44,096 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af wait-for-device
(INFO) 2016-12-07 18:44:44,099 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( test -d /sdcard );echo %$?'
(INFO) 2016-12-07 18:44:44,153 timeout_retry.WaitFor:107 condition 'sd_card_ready' met (0.1s)
(INFO) 2016-12-07 18:44:44,153 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( pm path android );echo %$?'
(INFO) 2016-12-07 18:44:44,711 timeout_retry.WaitFor:107 condition 'pm_ready' met (0.7s)
(INFO) 2016-12-07 18:44:44,711 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( getprop sys.boot_completed );echo %$?'
(INFO) 2016-12-07 18:44:44,778 timeout_retry.WaitFor:107 condition 'boot_completed' met (0.7s)
(INFO) 2016-12-07 18:44:44,787 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( su 0 ls /root && ! ls /root );echo %$?'
(INFO) 2016-12-07 18:44:44,927 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( cd /sys/devices/system/cpu && for CPU in cpu0 cpu1 cpu2 cpu3 cpu4 cpu5; do test -e "$CPU/cpufreq/scaling_governor" && echo performance > "$CPU/cpufreq/scaling_governor"; echo -n "%~%$?%~%"; done );echo %$?'
(INFO) 2016-12-07 18:44:45,003 perf_control._WriteEachCpuFile:116 Successfully set cpufreq/scaling_governor to 'performance' on: cpu0 cpu1 cpu2 cpu3 cpu4 cpu5
(INFO) 2016-12-07 18:44:45,003 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( ndc resolver flushdefaultif );echo %$?'
(INFO) 2016-12-07 18:44:45,104 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( logcat -c );echo %$?'
(INFO) 2016-12-07 18:44:45,205 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( ( dumpsys window windows )>/data/local/tmp/temp_file-86425b36b6abb );echo %$?'
(INFO) 2016-12-07 18:44:45,288 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af pull /data/local/tmp/temp_file-86425b36b6abb /b/swarm_slave/w/itJK4rCB/tmpEzRrx0/tmp_ReadFileWithPull
(INFO) 2016-12-07 18:44:45,451 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell 'rm -f /data/local/tmp/temp_file-86425b36b6abb'
(INFO) 2016-12-07 18:44:45,469 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( test -e /data/local/chrome-command-line );echo %$?'
(INFO) 2016-12-07 18:44:45,533 android_command_line_backend._WriteFile:107 Android app/browser startup args: chrome --js-flags=--expose-gc --enable-logging=stderr --disable-domain-blocking-for-3d-apis --disable-gpu-process-crash-limit --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:40831 --ignore-certificate-errors --disable-component-extensions-with-background-pages --disable-default-apps --enable-remote-debugging --disable-fre --disable-external-intent-requests
(INFO) 2016-12-07 18:44:45,534 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( test -d /data/local/chrome-command-line );echo %$?'
(INFO) 2016-12-07 18:44:45,589 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af push /b/swarm_slave/w/itJK4rCB/tmpHgXNhE /data/local/chrome-command-line
(INFO) 2016-12-07 18:44:45,734 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( am start -W -d about:blank -n org.chromium.chrome/com.google.android.apps.chrome.Main );echo %$?'
(INFO) 2016-12-07 18:44:46,999 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af forward --no-rebind tcp:33716 localabstract:chrome_devtools_remote
(INFO) 2016-12-07 18:44:47,316 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( rm -f /data/local/chrome-command-line );echo %$?'
(INFO) 2016-12-07 18:44:47,417 browser._LogBrowserInfo:113 OS: android M
(INFO) 2016-12-07 18:44:47,432 browser._LogBrowserInfo:117 Model: Nexus 5X
(INFO) 2016-12-07 18:44:47,432 browser._LogBrowserInfo:120 GPU device 0: VENDOR = 0x0 (Qualcomm), DEVICE = 0x0 (Adreno (TM) 418)
(INFO) 2016-12-07 18:44:47,432 browser._LogBrowserInfo:122 GPU Attributes:
(INFO) 2016-12-07 18:44:47,432 browser._LogBrowserInfo:124 adapter_luid : 0
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 amd_switchable : False
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 basic_info_state : 1
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 context_info_state : 1
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 direct_rendering : True
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 driver_date : 
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 driver_vendor : 
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 driver_version : 127.0
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 gl_extensions : GL_OES_EGL_image GL_OES_EGL_image_external GL_OES_EGL_sync GL_OES_vertex_half_float GL_OES_framebuffer_object GL_OES_rgb8_rgba8 GL_OES_compressed_ETC1_RGB8_texture GL_AMD_compressed_ATC_texture GL_KHR_texture_compression_astc_ldr GL_OES_texture_npot GL_EXT_texture_filter_anisotropic GL_EXT_texture_format_BGRA8888 GL_OES_texture_3D GL_EXT_color_buffer_float GL_EXT_color_buffer_half_float GL_QCOM_alpha_test GL_OES_depth24 GL_OES_packed_depth_stencil GL_OES_depth_texture GL_OES_depth_texture_cube_map GL_EXT_sRGB GL_OES_texture_float GL_OES_texture_float_linear GL_OES_texture_half_float GL_OES_texture_half_float_linear GL_EXT_texture_type_2_10_10_10_REV GL_EXT_texture_sRGB_decode GL_OES_element_index_uint GL_EXT_copy_image GL_EXT_geometry_shader GL_EXT_tessellation_shader GL_OES_texture_stencil8 GL_EXT_shader_io_blocks GL_OES_shader_image_atomic GL_OES_sample_variables GL_EXT_texture_border_clamp GL_EXT_multisampled_render_to_texture GL_OES_shader_multisample_interpolation GL_EXT_texture_cube_map_array GL_EXT_draw_buffers_indexed GL_EXT_gpu_shader5 GL_EXT_robustness GL_EXT_texture_buffer GL_OES_texture_storage_multisample_2d_array GL_OES_sample_shading GL_OES_get_program_binary GL_EXT_debug_label GL_KHR_blend_equation_advanced GL_KHR_blend_equation_advanced_coherent GL_QCOM_tiled_rendering GL_ANDROID_extension_pack_es31a GL_EXT_primitive_bounding_box GL_OES_standard_derivatives GL_OES_vertex_array_object GL_EXT_disjoint_timer_query GL_KHR_debug GL_EXT_YUV_target GL_EXT_sRGB_write_control GL_EXT_texture_norm16 GL_EXT_discard_framebuffer GL_OES_surfaceless_context GL_OVR_multiview GL_OVR_multiview2 GL_EXT_texture_sRGB_R8 GL_KHR_no_error GL_EXT_debug_marker OES_EGL_image_external_essl3 GL_OVR_multiview_multisampled_render_to_texture GL_EXT_buffer_storage 
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 gl_renderer : Adreno (TM) 418
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 gl_reset_notification_strategy: 33362
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 gl_vendor : Qualcomm
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 gl_version : OpenGL ES 3.1 V@127.0 (GIT@I8366cd0437)
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 gl_ws_extensions : 
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 gl_ws_vendor : 
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 gl_ws_version : 
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 in_process_gpu : True
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 initialization_time : 0
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 jpeg_decode_accelerator_supported: False
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 lenovo_dcute : False
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 max_msaa_samples : 4
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 optimus : False
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 passthrough_cmd_decoder: False
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 pixel_shader_version: 3.10
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 process_crash_count : 0
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 sandboxed : False
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 software_rendering : False
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 vertex_shader_version: 3.10
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:124 video_decode_accelerator_flags: 0
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:126 Feature Status:
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:128 2d_canvas : enabled
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:128 flash_3d : enabled
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:128 flash_stage3d : enabled
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:128 flash_stage3d_baseline: enabled
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:128 gpu_compositing : enabled
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:128 multiple_raster_threads: disabled_off
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:128 native_gpu_memory_buffers: disabled_software
(INFO) 2016-12-07 18:44:47,433 browser._LogBrowserInfo:128 rasterization : enabled
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:128 video_decode : enabled
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:128 video_encode : unavailable_software
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:128 vpx_decode : enabled
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:128 webgl : enabled
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:128 webgl2 : unavailable_off
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:130 Driver Bug Workarounds:
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 broken_egl_image_ref_counting
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 clear_uniforms_before_first_program_use
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 disable_blend_equation_advanced
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 disable_chromium_framebuffer_multisample
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 disable_depth_texture
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 disable_discard_framebuffer
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 disable_framebuffer_cmaa
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 disable_program_disk_cache
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 force_cube_map_positive_x_allocation
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 max_copy_texture_chromium_size_1048576
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 max_texture_size_limit_4096
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 scalarize_vec_and_mat_constructor_args
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 unbind_attachments_on_bound_render_fbo_delete
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 unbind_egl_context_to_flush_driver_caches
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 use_virtualized_gl_contexts
(INFO) 2016-12-07 18:44:47,434 browser._LogBrowserInfo:132 wake_up_gpu_before_drawing
ERROR
(INFO) 2016-12-07 18:45:02,432 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/forwarder_host --adb=/b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb --serial-id=00dd7fdd56bed3af --unmap 40831
(INFO) 2016-12-07 18:45:02,446 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( ps | grep -F org.chromium.chrome; echo "PIPESTATUS: ${PIPESTATUS[@]}" );echo %$?'
(INFO) 2016-12-07 18:45:02,547 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( ls /root );echo %$?'
(INFO) 2016-12-07 18:45:02,611 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( cd /sys/devices/system/cpu && for CPU in cpu0 cpu1 cpu2 cpu3 cpu4 cpu5; do test -e "$CPU/cpufreq/scaling_governor" && echo ondemand > "$CPU/cpufreq/scaling_governor"; echo -n "%~%$?%~%"; done );echo %$?'
(INFO) 2016-12-07 18:45:02,675 perf_control._WriteEachCpuFile:116 Successfully set cpufreq/scaling_governor to 'ondemand' on: cpu0 cpu1 cpu2 cpu3 cpu4 cpu5
(INFO) 2016-12-07 18:45:02,675 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( cd /sys/devices/system/cpu && for CPU in cpu0 cpu1 cpu2 cpu3 cpu4 cpu5; do cat "$CPU/online"; echo -n "%~%$?%~%"; done );echo %$?'
(INFO) 2016-12-07 18:45:02,742 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af shell '( p=org.chromium.chrome;if [[ "$(ps)" = *$p* ]]; then am force-stop $p; fi );echo %$?'
(INFO) 2016-12-07 18:45:03,543 cmd_helper._ValidateAndLogCommand:155 [host]> /b/swarm_slave/w/irKcgKuP/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s 00dd7fdd56bed3af forward --remove tcp:33716


In these three jobs:

https://build.chromium.org/p/tryserver.chromium.android/builders/android_optional_gpu_tests_rel/builds/1288
https://build.chromium.org/p/tryserver.chromium.android/builders/android_optional_gpu_tests_rel/builds/1285
https://build.chromium.org/p/tryserver.chromium.android/builders/android_optional_gpu_tests_rel/builds/1284

At some point, the browser stopped launching successfully, and all subsequent tests failed so slowly that the job timed out.

I suspect that the root cause here is the same as for  Issue 672382  and since that's blocking the main Chromium CQ I'll block this on that bug.