The following tests:

ContextLost.WebGLContextLostFromLoseContextExtension
ContextLost.WebGLContextLostFromQuantity

Both show this when run on the Nexus 5 bot:

(INFO) 2016-05-13 09:04:42,828 cmd_helper._ValidateAndLogCommand:153  [host]> /tmp/isolated_run5rG51b/third_party/catapult/devil/bin/deps/linux2/x86_64/bin/adb -s ZX1G22L2WM shell '( rm -f /data/local/tmp/content-shell-command-line );echo %$?'
(INFO) 2016-05-13 09:04:42,928 cache_temperature.EnsurePageCacheTemperature:29  PageCacheTemperature: any
Traceback (most recent call last):
  File "/tmp/isolated_run5rG51b/third_party/catapult/telemetry/telemetry/internal/story_runner.py", line 84, in _RunStoryAndProcessErrorIfNeeded
    state.RunStory(results)
  File "/tmp/isolated_run5rG51b/content/test/gpu/gpu_tests/gpu_test_base.py", line 111, in RunStory
    RunStoryWithRetries(GpuSharedPageState, self, results)
  File "/tmp/isolated_run5rG51b/content/test/gpu/gpu_tests/gpu_test_base.py", line 72, in RunStoryWithRetries
    super(cls, shared_page_state).RunStory(results)
  File "/tmp/isolated_run5rG51b/third_party/catapult/telemetry/telemetry/page/shared_page_state.py", line 330, in RunStory
    self._current_page.Run(self)
  File "/tmp/isolated_run5rG51b/third_party/catapult/telemetry/telemetry/page/__init__.py", line 95, in Run
    shared_state.page_test.RunNavigateSteps(self, current_tab)
  File "/tmp/isolated_run5rG51b/third_party/catapult/telemetry/telemetry/page/legacy_page_test.py", line 191, in RunNavigateSteps
    page.RunNavigateSteps(action_runner)
  File "/tmp/isolated_run5rG51b/content/test/gpu/gpu_tests/context_lost.py", line 306, in RunNavigateSteps
    'window.domAutomationController._loaded')
  File "/tmp/isolated_run5rG51b/third_party/catapult/telemetry/telemetry/internal/actions/action_runner.py", line 186, in WaitForJavaScriptCondition
    self._tab.WaitForJavaScriptExpression(condition, timeout_in_seconds)
  File "/tmp/isolated_run5rG51b/third_party/catapult/telemetry/telemetry/internal/browser/web_contents.py", line 136, in WaitForJavaScriptExpression
    e.message + '\n' + debug_message)
TimeoutException: Timed out while waiting 60s for IsJavaScriptExpressionTrue.
Console output:
(log) :29: Harness injected.
(warning) http://127.0.0.1:52052/webgl.html?query=forced_quantity_loss:0: [.Offscreen-For-WebGL-0xb4a1ec00]GL ERROR :GL_INVALID_OPERATION : glReadPixels: 


[  FAILED  ] ContextLost.WebGLContextLostFromQuantity (79015 ms)