[Swarming] Let test runner exit gracefully after test failures.

tools/testrunner/local/execution.py

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 198 matching lines @@
       test.run += 1
       test.output = result[1]
       pool.add([self._GetJob(test)])
     # Always update the perf database.
     return True
 
   def Run(self, jobs):
     self.indicator.Starting()
     self._RunInternal(jobs)
     self.indicator.Done()
-    if self.failed or self.remaining:
+    if self.failed:
       return 1
+    elif self.remaining:
+      return 2
     return 0
 
   def _RunInternal(self, jobs):
     pool = Pool(jobs)
     test_map = {}
     queued_exception = [None]
     def gen_tests():
       for test in self.tests:
         assert test.id >= 0
         test_map[test.id] = test
@@ skipping 58 matching lines @@
            test.suite.GetFlagsForTestCase(test, self.context) +
            self.context.extra_flags)
     return cmd
 
 
 class BreakNowException(Exception):
   def __init__(self, value):
     self.value = value
   def __str__(self):
     return repr(self.value)