Adding 3 attempts at starting the browser for a gpu integration test.

content/test/gpu/gpu_tests/gpu_integration_test_unittest.py

Index: content/test/gpu/gpu_tests/gpu_integration_test_unittest.py
diff --git a/content/test/gpu/gpu_tests/gpu_integration_test_unittest.py b/content/test/gpu/gpu_tests/gpu_integration_test_unittest.py
index 7d87ff89862b51ac2cf229a2f11c03504f232d7d..c62317566251953e49294f5170a01336e3ee6ac6 100644
--- a/content/test/gpu/gpu_tests/gpu_integration_test_unittest.py
+++ b/content/test/gpu/gpu_tests/gpu_integration_test_unittest.py
@@ -17,6 +17,7 @@ from gpu_tests import gpu_integration_test
 from gpu_tests import gpu_test_expectations
 
 _GLOBAL_TEST_COUNT = 0
+_GLOBAL_RESTART_CRASH = False
 
 class SimpleIntegrationUnittest(gpu_integration_test.GpuIntegrationTest):
   # Must be class-scoped since instances aren't reused across runs.
@@ -24,6 +25,8 @@ class SimpleIntegrationUnittest(gpu_integration_test.GpuIntegrationTest):
 
   _num_browser_starts = 0
 
+  _num_restart_failures = 0
+
   @classmethod
   def Name(cls):
     return 'simple_integration_unittest'
@@ -61,6 +64,9 @@ class SimpleIntegrationUnittest(gpu_integration_test.GpuIntegrationTest):
     yield ('expected_skip', 'failure.html', ())
     yield ('unexpected_failure', 'failure.html', ())
     yield ('unexpected_error', 'error.html', ())
+    # This test causes the browser to restart 2 times (max allowed 3) and then
+    # succeeds on the third attempt
+    yield ('restart', 'restart.html', ())
 
   @classmethod
   def _CreateExpectations(cls):
@@ -75,9 +81,26 @@ class SimpleIntegrationUnittest(gpu_integration_test.GpuIntegrationTest):
     super(SimpleIntegrationUnittest, cls).StartBrowser()
     cls._num_browser_starts += 1
 
+  @classmethod
+  def StopBrowser(cls):
+    global _GLOBAL_RESTART_CRASH
+    if _GLOBAL_RESTART_CRASH:
+      if cls._num_restart_failures < 2:
+        cls._num_restart_failures += 1
+        raise Exception
+      else:
+        _GLOBAL_RESTART_CRASH = False
+
+    super(SimpleIntegrationUnittest, cls).StopBrowser()
+
+
   def RunActualGpuTest(self, file_path, *args):
     if file_path == 'failure.html':
       self.fail('Expected failure')
+    elif file_path == 'restart.html':
+      global _GLOBAL_RESTART_CRASH
+      _GLOBAL_RESTART_CRASH = True
+      self._RestartBrowser("testing restart on failure")
     elif file_path == 'flaky.html':
       if self.__class__._num_flaky_runs_to_fail > 0:
         self.__class__._num_flaky_runs_to_fail -= 1
@@ -109,10 +132,12 @@ class GpuIntegrationTestUnittest(unittest.TestCase):
           'unexpected_error',
           'unexpected_failure'])
       self.assertEquals(test_result['successes'], [
-          'expected_flaky'])
+          'expected_flaky', 'restart'])
       self.assertEquals(test_result['valid'], True)
       # It might be nice to be more precise about the order of operations
       # with these browser restarts, but this is at least a start.
-      self.assertEquals(SimpleIntegrationUnittest._num_browser_starts, 6)
+      self.assertEquals(SimpleIntegrationUnittest._num_browser_starts, 7)
+      # Assert that we restarted the browser 2 times due to failure in restart
+      self.assertEquals(SimpleIntegrationUnittest._num_restart_failures, 2)
     finally:
       os.remove(temp_file_name)