Work around about:gpucrash tab crashes caused by impl-side painting.

content/test/gpu/gpu_tests/context_lost.py

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 import os
 
 from telemetry import test as test_module
 from telemetry.core import util
 from telemetry.page import page_set
 from telemetry.page import page_test
 
@@ skipping 54 matching lines @@
           raise page_test.Failure('Browser must support tab control')
         # Reset the test's state.
         tab.EvaluateJavaScript(
           'window.domAutomationController._succeeded = false');
         tab.EvaluateJavaScript(
           'window.domAutomationController._finished = false');
         # Crash the GPU process.
         new_tab = tab.browser.tabs.New()
         # To access these debug URLs from Telemetry, they have to be
         # written using the chrome:// scheme.
-        new_tab.Navigate('chrome://gpucrash')
+        # The try/except is a workaround for crbug.com/368107.
+        try:
+          new_tab.Navigate('chrome://gpucrash')
+        except (exceptions.TabCrashException, Exception):
+          print 'Tab crashed while navigating to chrome://gpucrash'
         # Activate the original tab and wait for completion.
         tab.Activate()
         completed = False
         try:
           util.WaitFor(lambda: tab.EvaluateJavaScript(
               'window.domAutomationController._finished'), wait_timeout)
           completed = True
         except util.TimeoutException:
           pass
-        new_tab.Close()
+        # The try/except is a workaround for crbug.com/368107.
+        try:
+          new_tab.Close()
+        except (exceptions.TabCrashException, Exception):
+          print 'Tab crashed while closing chrome://gpucrash'
         if not completed:
           raise page_test.Failure(
               'Test didn\'t complete (no context lost event?)')
         if not tab.EvaluateJavaScript(
           'window.domAutomationController._succeeded'):
           raise page_test.Failure(
             'Test failed (context not restored properly?)')
 
 class ContextLost(test_module.Test):
   enabled = True
@@ skipping 26 matching lines @@
           'navigate_steps': [
             { 'action': 'navigate' },
             { 'action': 'wait',
               'javascript': 'window.domAutomationController._finished' }
           ],
           'kill_gpu_process': False
         },
       ]
     }
     return page_set.PageSet.FromDict(page_set_dict, data_path)